Senior Software Engineer - SQL, Python, Adobe Flex, Object-Oriented Programming
Senior Software Engineer - SQL, Python, Adobe Flex, Object-Oriented Programming Job Responsibilities The Sr. Software Developer will be responsible for the development of the WordStream suite of products. Development is done primarily using Python on the server, and with Adobe Flex or HTML/AJAX as a Rich Internet Application (RIA) frontend. Typical day-to-day activities include implementing new features in our products, which involve: * Development of processes to extract relevant data from input sources * Design of relational data storage models * Implementation of data processing algorithms * Development of AMF remoting methods, used for client/server connectivity * Development of graphical user interfaces Qualifications The candidate must have top-notch software development skills. Prior experience in Python or Adobe Flex is not a strict requirement, experience in related technologies will be accepted. Please note, only candidates with a bachelor's degree in computer science or engineering, or, a very substantial amount of related technical coursework and work experience in a related field will be considered. Prior experience working on web analytics applications, search engines, content management systems or other Web publishing systems is a plus. Required Skills: Structured Query Language (SQL), Object-Oriented Programming Bonus Skills: Python, Adobe Flex, SQLite, Open-Source software development, Git, Object-Relational Mapping (ORM), Postgres SQL, AJAX, HTML, Search Engine Optimization (SEO) or Search Engine Marketing (SEM) Type of Position: Full-time or Contract-to-hire Travel Required: None Location: Worldwide (telecommunication) Position Title: Sr. Software Developer Compensation and Benefits: Competitive salary based on experience. Employees will have an opportunity to participate in the company's stock option plan. How To Apply To apply for the Senior Software Engineer position, send a resume and cover letter to jobs at WordStream dot com. About WordStream WordStream is a venture-backed startup engaged in providing search engine marketing software solutions for PPC/SEM and SEO. Our patented, innovative software-as-a-service applications automate the manual, repetitive work involved in search engine optimization, saving time and enabling customers to improve ROI on search marketing objectives in a consistent and repeatable manner. For more information: Please visit http://www.wordstream.com -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
Fwd: VPython turns 5
Hi Folks, I got this from Bruce Sherwood and thought others might be interested. -steve Begin forwarded message: From: Bruce Sherwood bruce_sherw...@ncsu.edu Date: December 9, 2008 11:01:05 AM EST To: Steve Spicklemire st...@spvi.com Subject: Advertising - At vpython.org there is now available the Visual 5.0 release candidate for Windows, Mac 10.5, and Linux. The native-mode Mac version does not use X11 nor depend on Fink. Major new features include opacity, local lighting, and materials such as wood. Of interest to researchers is the new points object which is useful for representing data in 3D. Visual 5.0 was created by David Scherer and Bruce Sherwood. Jonathan Brandmeyer while an undergraduate at NCSU provided support in Visual 4beta for opacity, local lighting, and textures, and made some important architectural changes, but had to stop work on the project before it was completed. Further development has led to API changes which are incompatible with the Visual 4beta release, so this release is called version 5 instead of 4. P.S. You will see shader errors and/or the inability to display materials such as wood if your graphics hardware does not support Pixel Shader 3.0. The key point is this statement in the Visual 5.0 help (see the What's new section or the materials section): Materials will work with graphics cards that support Pixel Shader 3.0 (PS 3.0). For details, see http://en.wikipedia.org/wiki/Pixel_shader#Hardware. Some materials may work with graphics cards that support PS 2.0, but other materials may need to be manually disabled; see instructions in the site-settings.py module in the Visual package in your site-packages folder. If the graphics hardware does not support pixel shaders, the material property is ignored. If you think you should be able to use materials but have trouble with their display or performance, we highly recommend upgrading your video card drivers to the latest version. -- http://mail.python.org/mailman/listinfo/python-announce-list Support the Python Software Foundation: http://www.python.org/psf/donations.html
Re: Windows PE and Python 2.6 (Side-by-Side error)
Martin v. Löwis schrieb: Has anyone an idea? You should not install for all users before copying it, but just for me. Regards, Martin This works! Thank you very much! (Sorry for the delay. I had been on a conference, than I was ill and than, there were more urgent things...) But now PyScripter may not use Python 2.6 internally. E. g., if I load a python-dll (import bz2) I receise an Runtime ERROR! R6034... Again, thanx a lot Werner -- http://mail.python.org/mailman/listinfo/python-list
Re: eval() and global variables
Juan Pablo Romero Méndez wrote: Suppose this function is given: def f(x,y): return x+y+k Is it possible to somehow assign a value to k without resorting to making k global? You can replace the function's global dictionary: def f(x, y): ... return x+y+k ... function = type(f) function(f.func_code, dict(k=1))(2, 3) 6 k Traceback (most recent call last): File stdin, line 1, in module NameError: name 'k' is not defined This is a hack, of course. Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: mod_python resources
On Dec 17, 11:10 am, Дамјан Георгиевски gdam...@gmail.com wrote: I'm trying again because I'm stubborn. Maybe the fourth time will be the charm... Are there any good tutorials out there for setting up Apache with mod_python? mod_python is depreceated, nobody uses it. usemod_wsgihttp://www.modwsgi.org/ The mod_python package is not deprecated, although it could be said to be sleeping at the moment. You'll also probably still find that more new people choose mod_python over mod_wsgi. This is because it has the more obvious name to look for when Googling. It also has publisher and PSP high level handler which are still attractive to many as they are more lightweight and easier to get into than the large WSGI frameworks. Finally, the Django folks still recommend in their documentation to use mod_python. Anyway, if wanting to host a WSGI capable application, using mod_wsgi would be the more obvious choice. If wanting to write your own framework, or work at low level, basing it on WSGI rather than mod_python specific APIs would certainly be a better long term direction to take. Graham -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
On Dec 17, 9:39 pm, aka alexoploca...@gmail.com wrote: Due to being in a hurry I didn't paste correctly (sorry). The intention is to put values of column 1 (id) in the roles list, therefore appending within the loop, to fill a session var. The complete code is: It's *not* complete. It's missing import csv. roles = [] inp = 'C:/temp/test.csv' try: fp = open(inp, 'rb') reader = csv.reader(fp, dialect='excel', delimiter=';') for r in reader: roles.append(r) ## ultimately should be something like r.id or r[0] ## first row of csv file should be skipped because of column names except: msg = 'Something's wrong with the csv.reader' But you don't print the message! In any case, using the try/except like that *hides* any useful diagnostic information; it gives only an indication that something is wrong, but not what is wrong and where it is wrong. If you throw away the try/except, you will get a more meaningful message -- possibly that csv is not defined!! -- and the traceback will tell you in which line the error occured. return dict(file=inp,roles=str(roles)) Why do you think that you need (a) that complicated expression (b) the str() call? Assuming you are intending to make a function out of all that, what's wrong with returning a (simple) tuple: return inp, roles ? The above 'return' statement is not inside a function/method. You would have got this message: SyntaxError: 'return' outside function People will very soon lose patience with you if you persist in not posting the actual code that you ran. The roles list isn't populated at all :( This could mean (if the code that was posted is moderately similar to that which was run) that the error happened before the first time that roles.append(r) was executed ;-) Please divulge the contents of test.csv -- but not if it's huge! Considering trying to get your code to work first with a data file of close-to-minimal size and complexity, like this: 8--- id,other_info tom,1 dick,2 harry,3 8--- By the way, you mentioned the UnicodeReader class in your original post, but you don't seem to use it ... -- http://mail.python.org/mailman/listinfo/python-list
Re: Python, XML and XPath
Hole wrote: Hi all, I hope this is not an overasked question but I find myself quite confused about python xml management (I have to use python for a project and I come from java world, you know...where frameworks, libraries and tools to use are standard de iure or standard de facto). snip I suggest you use one of the available binary builds for windows: http://pypi.python.org/pypi/lxml/2.1 Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: Selecting a different superclass
psaff...@googlemail.com wrote: The problem is that IDPointSet and MicroArrayPointSet will need to inherit from PointSet or TraceablePointSet based on whether I'm handling traceable points or not. Can I select a superclass conditionally like this in Python? Am I trying to do something really evil here? Any other bright ideas on my application also welcome. I think you should investigate something different than subclassing, like a Strategy domain pattern or something similar. -- http://mail.python.org/mailman/listinfo/python-list
Re: Selecting a different superclass
Marco Mariani wrote: I think you should investigate something different than subclassing, like a Strategy domain pattern or something similar. s/domain/design/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
I think there is a simpler answer to all this(not to take away from the other ones here though which are all great). When writing procedural code how would you like it if vars inside functions were automatically global. Your code with be blowing chunks in no time. Thats the reason for global declarations and instance.var :) -- http://mail.python.org/mailman/listinfo/python-list
Re: Transferring a file over sockets
Ferdinand Sousa wrote:
I am using sockets to transfer a file over LAN. There are 2 scripts, the
server opens a listens for connection and the client is run on another
machine. I always make sure the server is run first. The strange thing is
that if the the server script is double-clicked and executed (run in a
console with title %Python path%python.exe) the output file saved on the
server is truncated. It works just fine if you open the server script in
IDLE and then run it. The client script can be run in either way, it still
works. You could try using any arbitrary file to test this behaviour after
changing the file name in both the scripts.
A couple of things:
* Are you aware that there's no particular guarantee
that what's sent along a socket in one write will
be received in one read? There's a HOWTO here if
you're interested:
http://docs.python.org/dev/howto/sockets.html
* Also, unless this is an exercise for yourself in investigating
how sockets work, (in which case... read the docs :)), you might
consider that you're reinventing the wheel not a little. But
perhaps you knew that?
TJG
==
# file receiver
# work in progress
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
HOST = '192.168.1.17'
PORT = 31400
s.bind((HOST, PORT))
s.listen(3)
conn, addr = s.accept()
print 'conn at address',addr
conn.send('READY')
f = open('C:\\Documents and Settings\\USER\\Desktop\\test.pdf','wb')
fsize=int(conn.recv(8))
print 'File size',fsize
f.write(conn.recv(fsize))
f.close()
conn.close()
s.close()
raw_input('Press any key to exit')
===
# file sender !!!
# Work in progress
import socket, os
from stat import ST_SIZE
HOST = '192.168.1.17'
PORT = 31400 # Arbitrary non-privileged port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST,PORT))
if s.recv(5)!='READY':
raw_input('Unable to connect \n\n Press any key to exit ...')
s.close()
exit()
f=open('C:\\Documents and Settings\\USER\\Desktop\\t.pdf', 'rb')
fsize=os.stat(f.name)[ST_SIZE]
s.send(str(fsize))
s.send(f.read())
s.close()
f.close()
===
Thanks for reading!!
Best regards,
Ferdi
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--
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Re: Why no lexical scoping for a method within a class?
walterbyrd walterb...@iname.com wrote in message news:518b9dd9-69c5-4d5b-bd5f-ad567be62...@b38g2000prf.googlegroups.com... However in the methods are within a class, the scoping seems to work differently. Not really, self is a formal parameter to the function. It would be a strange language where a function's own arguments weren't in scope. def b(self): print self.x Try changing it to: def b(somethingotherthanself): print self.x -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
On Dec 17, 5:16 pm, Rominsky john.romin...@gmail.com wrote: I am trying to use dir to generate a list of methods, variables, etc. I would like to be able to go through the list and seperate the objects by type using the type() command, but the dir command returns a list of strings. When I ask for the type of an element, the answer is always string. How do I point at the variables themselves. A quick example is: a = 5 b = 2.0 c = 'c' lst = dir() for el in lst: print type(el) Right now I am understandably getting all types being output as strings, how do i get the type of the actual objects returned from dir ()? The builtin functions locals and globals will both return a dictionary whose keys are the variable names and values are the items corresponding to those keys; locals()['b'] 2.0 -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
--- On Wed, 12/17/08, Rominsky john.romin...@gmail.com wrote: From: Rominsky john.romin...@gmail.com Subject: getting object instead of string from dir() To: python-list@python.org Date: Wednesday, December 17, 2008, 12:16 PM I am trying to use dir to generate a list of methods, variables, etc. I would like to be able to go through the list and seperate the objects by type using the type() command, but the dir command returns a list of strings. When I ask for the type of an element, the answer is always string. How do I point at the variables themselves. A quick example is: a = 5 b = 2.0 c = 'c' lst = dir() for el in lst: print type(el) Right now I am understandably getting all types being output as strings, how do i get the type of the actual objects returned from dir ()? -- http://mail.python.org/mailman/listinfo/python-list Forgive me if you are well aware of this, just thought i'd chime in with the Duck typing speech: Pythonic programming style that determines an object's type by inspection of its method or attribute signature rather than by explicit relationship to some type object (If it looks like a duck and quacks like a duck, it must be a duck.) By emphasizing interfaces rather than specific types, well-designed code improves its flexibility by allowing polymorphic substitution. Duck-typing avoids tests using type() or isinstance(). Instead, it typically employs the EAFP (Easier to Ask Forgiveness than Permission) style of programming. http://en.wikipedia.org/wiki/Duck_typing -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Dec 18, 2:19 am, walterbyrd walterb...@iname.com wrote: For a language as well structured as Python, this seems somewhat sloppy, and inconsistant. Or is there some good reason for this? Here is what I mean: def a(): x = 99 print x def b(): print x a() b() # raises an exception because x is not defined. However in the methods are within a class, the scoping seems to work differently. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() i.a() i.b() # this works, why no lexical scoping? Two questions for you: (1) If you were to change the sloppy inconsistent scoping mechanism in classes, what would you change it to? (2) What do you think of the following: class ab(): def a(self): self.x = 99 print self.x def b(me): print me.x ? -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
Rominsky schrieb: I am trying to use dir to generate a list of methods, variables, etc. I would like to be able to go through the list and seperate the objects by type using the type() command, but the dir command returns a list of strings. When I ask for the type of an element, the answer is always string. How do I point at the variables themselves. A quick example is: a = 5 b = 2.0 c = 'c' lst = dir() for el in lst: print type(el) for name, obj in vars().iteritems(): print name, obj Christian -- http://mail.python.org/mailman/listinfo/python-list
Re: Python, XML and XPath
I need to use XML parsing with xpath: a simple xml reader. You can try lxml, have a look herehttp://codespeak.net/lxml/xpathxslt.html Thanks a lot to everyone! -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Dec 17, 10:00 am, r rt8...@gmail.com wrote: When writing procedural code how would you like it if vars inside functions were automatically global. Your code with be blowing chunks in no time. That was my point - I consider python's ordinary use of lexical scoping to be a good thing, and I was wondering why this good thing was not used in classes, as well as outside of classes. -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Dec 17, 9:04 am, rdmur...@bitdance.com wrote: Yes. It's called Object Oriented Programming. I think you mean it's *Python* Object Oriented Programming. I am not sure that every other OO language works like that. -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Dec 17, 10:17 am, Richard Brodie r.bro...@rl.ac.uk wrote: Not really, self is a formal parameter to the function. It would be a strange language where a function's own arguments weren't in scope. Thank you, that makes sense to me. -- http://mail.python.org/mailman/listinfo/python-list
Re: Relative imports in Python 3.0
On Dec 17, 4:01 am, Nicholas nicholas.c...@gmail.com wrote: Imagine a module that looks like ModuleDir __init__.py a.py b.py In python 2.x I used to have tests at the end of each of my modules, so that module b.py might look something like import a .. .. if __name__ == '__main__': runtests() But under Python 3.0 this seems impossible. For usual use import a.py has to become the line: from . import a But if I use that form it is no longer possible to run b.py as a standalone script without raising an error about using relative imports. I am sure I am not the first to run into this issue, but what is the solution? Use absolute imports: from ModuleDir import a Best wishes, Nicholas -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
Hi John, thanks. You're right, I didn't past the method header because I thought it didn't matter when the input filename is hardcoded. The try/except isn't very helpful indeed so I commented it out. You're right I wrongly referred to the UnicodeReader class in my first post because that's ultimately where I want to go so I outcommented it here for you to see. The fact is that neither csv.reader nor the UnicodeReader will read the file, while writing with the UnicodeWriter works like a charm. That's why I put str() around roles to see any content. I simplified the csv-file by cutting off columns without result. The file looks now like: id;company;department 12;Cadillac;Research 11;Ford;Accounting 10;Chrysler;Sales The dictionary on the return is because this code is part of my TurboGears application. The entire method is: import csv from utilities.urw import UnicodeWriter, UnicodeReader @expose(allow_json=True) def import_roles(self, input=None, *args, **kwargs): inp = 'C:/temp/test.csv' roles = [] msg = '' ## try: fp = open(inp, 'rb') reader = csv.reader(fp, dialect='excel', delimiter=';') ## reader = UnicodeReader(fp, dialect='excel', delimiter=';') for r in reader: roles.append(r[0]) fp.close() ## except: ## msg = Something's wrong with the csv.reader return dict(filepath=inp, roles=str(roles), msg=msg) csv.reader results in: for r in reader: Error: line contains NULL byte Use of UnicodeReader results in: UnicodeDecodeError: 'utf8' codec can't decode byte 0xff in position 0: unexpected code byte Will post only complete code from now on thanks. -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
Hi John, thanks. You're right, I didn't past the method header because I thought it didn't matter when the input filename is hardcoded. The try/except isn't very helpful indeed so I commented it out. You're right I wrongly referred to the UnicodeReader class in my first post because that's ultimately where I want to go so I outcommented it here for you to see. The fact is that neither csv.reader nor the UnicodeReader will read the file, while writing with the UnicodeWriter works like a charm. That's why I put str() around roles to see any content. I simplified the csv-file by cutting off columns without result. The file looks now like: id;company;department 12;Cadillac;Research 11;Ford;Accounting 10;Chrysler;Sales The dictionary on the return is because this code is part of my TurboGears application. The entire method is: import csv from utilities.urw import UnicodeWriter, UnicodeReader @expose(allow_json=True) def import_roles(self, input=None, *args, **kwargs): inp = 'C:/temp/test.csv' roles = [] msg = '' ## try: fp = open(inp, 'rb') reader = csv.reader(fp, dialect='excel', delimiter=';') ## reader = UnicodeReader(fp, dialect='excel', delimiter=';') for r in reader: roles.append(r[0]) fp.close() ## except: ## msg = Something's wrong with the csv.reader return dict(filepath=inp, roles=str(roles), msg=msg) csv.reader results in: for r in myreader: Error: line contains NULL byte Use of UnicodeReader results in: UnicodeDecodeError: 'utf8' codec can't decode byte 0xff in position 0: unexpected code byte Will post only complete code from now on thanks. -- http://mail.python.org/mailman/listinfo/python-list
Re: OT: Binary tree logarithms properties
Mr.SpOOn wrote: Hi, I'm searching for a clear explanation of binary tree properties, expecially the ones related to logarithms. For example, I know that in a tree with 2n-1 nodes, we have log(n) levels, from 0 to log(n). A *complete* binary tree with n levels has 2**n - 1 nodes. This is easily shown by induction. (Try Wikipedia for induction proof if you are not familiar with such.) So, if k is the level, the nodes on a level have indexes between 2^k and 2^(k+1)-1. For k=0 we have 2 and 3. For k=1 we have 4, 5, 6, 7 and so on. Nodes only have single number indexes if you arrange them linearly. Then the index depends on how you arrange them, whether you start the array indexes with 0 or 1, and whether you start the level numbers with 0 or 1. Call the breadth-first sequence bf. Then the 1-based slice for 1-first level k is bf[2**(k-1):2**k)]. Again, proof by induction. Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: The rule of literal string
Thank you, Chris! You have made me learn more about Python. -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
Due to being in a hurry I didn't paste correctly (sorry). The intention is to parse a csv file and (ultimately) put values of column 1 (id) in a list (so I need to append in the loop) that will be used to fill a session var. The complete code is: roles = [] inp = 'C:/temp/test.csv' try: fp = open(inp, 'rb') reader = csv.reader(fp, dialect='excel', delimiter=';') for r in reader: roles.append(r) ## ultimately should be something like r.id ## first row of csv file should be skipped because of column names or r[0] except: msg = 'Something's wrong with the csv.reader' return dict(file=inp,roles=str(roles)) The roles list isn't populated at all :( -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
Due to being in a hurry I didn't paste correctly (sorry). The intention is to put values of column 1 (id) in the roles list, therefore appending within the loop, to fill a session var. The complete code is: roles = [] inp = 'C:/temp/test.csv' try: fp = open(inp, 'rb') reader = csv.reader(fp, dialect='excel', delimiter=';') for r in reader: roles.append(r) ## ultimately should be something like r.id or r[0] ## first row of csv file should be skipped because of column names except: msg = 'Something's wrong with the csv.reader' return dict(file=inp,roles=str(roles)) The roles list isn't populated at all :( -- http://mail.python.org/mailman/listinfo/python-list
Re: Relative imports in Python 3.0
nicholas.c...@gmail.com wrote:
Imagine a module that looks like
ModuleDir
__init__.py
a.py
b.py
In python 2.x I used to have tests at the end of each of my modules,
so that module b.py might look something like
import a
..
..
if __name__ == '__main__':
runtests()
But under Python 3.0 this seems impossible. For usual use import a.py
has to become the line:
from . import a
But if I use that form it is no longer possible to run b.py as a
standalone script without raising an error about using relative
imports.
I am sure I am not the first to run into this issue, but what is the
solution?
Best wishes,
Nicholas
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Sorry for the duplicate, sent to wrong email.
Python 3 (and I think 2.6) now use absolute import when using a 'import
blah' statement.
if ('.' in __name__) or hasattr(globals, '__path__'):
from . import a
else:
import a
If '__name__' has a'.' then it is either a package or a module in a
package, in which case relative imports can be used. If it does not
have a '.' it may still be a package but the '__init__.py' file, in
which case the module has a '__path__' attribute, so relative imports
can be used. Otherwise it is not a package or in a package so absolute
imports must used. Also, since it is not in a package it is assumed
that it is top module (__main__) or possible module imported from the
top that is not in a package, such as a.py doing an 'import b', b would
be a module but not a package so still probably need absolute imports,
my guess anyway.
But I also think that 'from . import a' would be nice if it would work
from non-packages as well, meaning just 'import a' if it is a non-package.
Brian A. Vanderburg II
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Re: Why no lexical scoping for a method within a class?
On Dec 17, 12:20 pm, walterbyrd walterb...@iname.com wrote: On Dec 17, 10:00 am, r rt8...@gmail.com wrote: When writing procedural code how would you like it if vars inside functions were automatically global. Your code with be blowing chunks in no time. That was my point - I consider python's ordinary use of lexical scoping to be a good thing, and I was wondering why this good thing was not used in classes, as well as outside of classes. The whole point for even writing a class is for shared attributes. Write procedural code if you don't like classes. When ever you see self.var think of it as Class.instance(var)... makes total sense to me? Obliviously you have not done much procedural coding or you would know why this HAS to be. sorry if i sound rude. -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Dec 17, 8:41 am, prueba...@latinmail.com wrote: If scoping worked as you want, how, pray tell, would you define object attributes?- Hide quoted text - I suppose you could do this: class className(): varname = whatever def fname(self, varname): . . . . Instead of having variable defined within methods to be global everywhere within the class. Anyway, it's not a matter of what I like, I am just trying to understand the reason behind the scoping rules. -- http://mail.python.org/mailman/listinfo/python-list
Relative imports in Python 3.0
Imagine a module that looks like ModuleDir __init__.py a.py b.py In python 2.x I used to have tests at the end of each of my modules, so that module b.py might look something like import a .. .. if __name__ == '__main__': runtests() But under Python 3.0 this seems impossible. For usual use import a.py has to become the line: from . import a But if I use that form it is no longer possible to run b.py as a standalone script without raising an error about using relative imports. I am sure I am not the first to run into this issue, but what is the solution? Best wishes, Nicholas -- http://mail.python.org/mailman/listinfo/python-list
Re: Python, XML and XPath
Diez B. Roggisch wrote: Hole wrote: Hi all, I hope this is not an overasked question but I find myself quite confused about python xml management (I have to use python for a project and I come from java world, you know...where frameworks, libraries and tools to use are standard de iure or standard de facto). snip I suggest you use one of the available binary builds for windows: http://pypi.python.org/pypi/lxml/2.1 Most probably better: http://pypi.python.org/pypi/lxml/2.1.3 Diez -- http://mail.python.org/mailman/listinfo/python-list
Re: Managing timing in Python calls
Interesting stuff - I hadn't come across the 'with' syntax before, so
I've learned something already.
I was briefly excited to learn about the callLater command which is just
a convenience class for the wxTimer class. It seems to be pretty much
a parallel of the
var t = window.setTimeout( function () { do_when_timed_out}
sort of thing in AJAX.
However, as is well grumbled on the 'net, you can't use wxTimer from a
non-main thread. So that dropped off my plate.
But getting my head around my AJAX problem versus my python
implementation, I realized my use of those javascript structures were
really just used because javascript doesn't allow any threading at all.
With Python, just having my other processing path in a thread is enough,
and I can use the brutish time.sleep() function, without worrying about
blocking the processing of my mainline (UI) thread. So I'm able to proceed.
I do want to know more about the 'with' command tho' so I'll look into that.
Thx again.
Ross.
cmdrrickhun...@yaho.com wrote:
I believe WxTimerEvent is handled using the event queue, which isn't
going to do what you want. An event which goes through the queue does
not get processed until you return to the queue.
What you want to do is actually a rather difficult task to do
generically. Should the task be interrupted immediately? Or is a
tiny latency acceptable? Should the function being terminated get to
handle its own termination? Or should the termination be forced on
it. What sort of overhead is acceptable for this set_timeout
behavior?
I would not be surprised if there isn't a built in solution, because
its so hard, but rather built in tools which can be used to do it.
If your timeouts are on the order of seconds, you might be able to
just check time.time() at the begining, and compare it to the current
time later in the function. This could be on the main thread or on a
worker thread.
If you need better handling, you may want to look at how condition
variables and such work.
Finally, thread has a function to send a Keyboard Interrupt to the
main thread. I believe you could do your work on the main thread, and
catch the interrupt.
Background tasks are not easy to implement in any language (other
than perhaps AJAX ;-) ).
Remember, Python does not support truly simultaneous threads. It
actually does timeslices of about 100 operations. Any solution you
choose should work given this information.
And as for a nicer construct, I personally just learned of how to
handle the with command. I could see something like
class Timeout:
def __init__(self, t):
self.t = t
def __enter__(self):
self.start = time.time()
def __exit__(self, x, y, z):
return None
def __nonzero__(self):
return time.time() - self.start = self.t
def doSomethingLong(timeout = True): # true guarentees bailout never
occurs
while timeout:
doAnIteration()
with Timeout(3) as t:
doSomethingLong(t)
and have your Timeout class have a flag which it sets when
doSomethingLong needs to bail out, using whatever method is best for
your particular application. This is, of course pseudocode - I've not
run it through python msyself. Hopefully any errors are obvious
enough that you can work around them.
--
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Re: Python is slow
On Dec 10, 1:42 pm, cm_gui cmg...@gmail.com wrote: http://blog.kowalczyk.info/blog/2008/07/05/why-google-should-sponsor-... I fully agree with Krzysztof Kowalczyk . Can't they build a faster VM for Python since they love the language so much? Python is SLOW. And I am not comparing it with compiled languages like C. Python is even slower than PHP! Just go to any Python website and you will know. An example is:http://www2.ljworld.com/ And this site is created by the creators of Django! And it is not just this Python site that is slow. There are many many Python sites which are very slow. And please don’t say that it could be the web hosting or the server which is slow — because when so many Python sites are slower than PHP sites, it couldn’t be the web hosting. Also, Zope/Plone is even slower. Python is slow. Very slow. I did a DataBase consult with MySQLdb and PHP with 30 rows and who you think was the better and faster, YES, Python for almost 10 seconds, and I have to configure the php.ini for PHP could show me the DATA. He is just a futile troll frustrated with Python. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 3.0 crashes displaying Unicode at interactive prompt
Assuming those survived the switch to 3.0, you can use site.py und sys.displayhook to customize to the old behaviour (i.e. change it to a version using ascii instead of repr). Since this only affects interactive use, it's also no problem for portability of code, unlike solutions like forcing the defaultencoding etc. -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
John, this is the actual code I ran in TurboGears which is a Python framework. I should have left away the import statements. Trust me, the problem isn't in there because the UnicodeWriter is functioning perfectly. I did allready sanitate the csv file to these four lines in Notepad so there isn't anything more than this: id;company;department 12;Cadillac;Research 11;Ford;Accounting 10;Chrysler;Sales The only possible problematic lines are marked # here: def import_roles(self, input=None, *args, **kwargs): inp = 'C:/temp/test.csv' roles = [] msg = '' ## try: fp = open(inp, 'rb') # reader = csv.reader(fp, dialect='excel', delimiter=';') # ## reader = UnicodeReader(fp, dialect='excel', delimiter=';') # for r in reader: roles.append(r[0]) # fp.close() ## except: ## msg = Something's wrong with the csv.reader return dict(filepath=inp, roles=str(roles), msg=msg) Yeah rdmur, I'll have a look at the Python commandline. -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
On Dec 17, 10:59 am, Christian Heimes li...@cheimes.de wrote:
Rominsky schrieb:
I am trying to use dir to generate a list of methods, variables, etc.
I would like to be able to go through the list and seperate the
objects by type using the type() command, but the dir command returns
a list of strings. When I ask for the type of an element, the answer
is always string. How do I point at the variables themselves. A
quick example is:
a = 5
b = 2.0
c = 'c'
lst = dir()
for el in lst:
print type(el)
for name, obj in vars().iteritems():
print name, obj
Christian
I do have some understanding of the pythonic methodology of
programming, though by far I still don't consider myself an expert.
The problem at hand is that I am coming from a matlab world and trying
to drag my coworkers with me. I have gotten a lot of them excited
about using python for this work, but the biggest gripe everytime is
they want their matlab ide. I am trying to experiment with making
similar pieces of the ide, in particular I am working on the workspace
window which lists all the current variables in the namespace, along
with their type, size, value, etc I am trying to create a python
equivalent. I can get dir to list all the variables names in a list
of strings, but I am trying to get more info them. hence the desire
to do a type command on them. I like the locals and globals commands,
but I am still trying to get more info. I have started using the eval
command with the strings, which is working, but I am curious if there
is a better or more elegant way of getting the info. The eval example
would be something like:
a = 5
b = 2.0
c = 'c'
lst = dir()
for el in lst:
print el + '\t' + str(eval('type(%s)'%el))
It works, now I am curious if there is a better way.
--
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Re: Transferring a file over sockets
Ferdinand Sousa wrote:
==
.# file receiver
# work in progress
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
HOST = '192.168.1.17'
PORT = 31400
s.bind((HOST, PORT))
s.listen(3)
conn, addr = s.accept()
print 'conn at address',addr
conn.send('READY')
f = open('C:\\Documents and Settings\\USER\\Desktop\\test.pdf','wb')
fsize=int(conn.recv(8))
print 'File size',fsize
f.write(conn.recv(fsize))
This recv is not guaranteed to actually receive the number of
characters you are asking for - it will stop when it has received that
many, yes, but it may return with less, or even none if there is a
time out set.
The TCP is a more or less featureless stream of characters.
Consider including a start marker so you know where the lesson starts.
If you do this, consider the possibility of having a false sync.
Sending/receiving the length is good - also google for netstring
Google for escaping.
Consider writing a loop to receive until the required length has been
received - look at the docs for the recv function - it can tell you how
much has been received.
f.close()
conn.close()
s.close()
raw_input('Press any key to exit')
===
# file sender !!!
# Work in progress
import socket, os
from stat import ST_SIZE
HOST = '192.168.1.17'
PORT = 31400 # Arbitrary non-privileged port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST,PORT))
if s.recv(5)!='READY':
raw_input('Unable to connect \n\n Press any key to exit ...')
s.close()
exit()
f=open('C:\\Documents and Settings\\USER\\Desktop\\t.pdf', 'rb')
fsize=os.stat(f.name)[ST_SIZE]
s.send(str(fsize))
s.send(f.read())
Are you sure that the send will send all the chars
that you ask it to send?
If yes - why do you think this?
What are the values that the send can return?
s.close()
f.close()
===
hth - Hendrik
--
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Re: Transferring a file over sockets
Hendrik van Rooyen wrote:
Ferdinand Sousa wrote:
==
.# file receiver
# work in progress
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
HOST = '192.168.1.17'
PORT = 31400
s.bind((HOST, PORT))
s.listen(3)
conn, addr = s.accept()
print 'conn at address',addr
conn.send('READY')
f = open('C:\\Documents and Settings\\USER\\Desktop\\test.pdf','wb')
fsize=int(conn.recv(8))
print 'File size',fsize
f.write(conn.recv(fsize))
This recv is not guaranteed to actually receive the number of
characters you are asking for - it will stop when it has received that
many, yes, but it may return with less, or even none if there is a
time out set.
The TCP is a more or less featureless stream of characters.
Consider including a start marker so you know where the lesson starts.
If you do this, consider the possibility of having a false sync.
Sending/receiving the length is good - also google for netstring
Google for escaping.
Consider writing a loop to receive until the required length has been
received - look at the docs for the recv function - it can tell you how
much has been received.
f.close()
conn.close()
s.close()
raw_input('Press any key to exit')
===
# file sender !!!
# Work in progress
import socket, os
from stat import ST_SIZE
HOST = '192.168.1.17'
PORT = 31400 # Arbitrary non-privileged port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST,PORT))
if s.recv(5)!='READY':
raw_input('Unable to connect \n\n Press any key to exit ...')
s.close()
exit()
f=open('C:\\Documents and Settings\\USER\\Desktop\\t.pdf', 'rb')
fsize=os.stat(f.name)[ST_SIZE]
s.send(str(fsize))
s.send(f.read())
Are you sure that the send will send all the chars
that you ask it to send?
If yes - why do you think this?
What are the values that the send can return?
s.close()
f.close()
===
You're also sending the length as a bytestring str(fsize), which will
have an unknown length, but you're receiving the length as exactly 8
bytes. Either mark the end of the length in some way (with '\n'?) and
look for that when receiving, or pad what you send to exactly 8 bytes
(str(fsize).zfill(8)).
--
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[Help] The pywinauto Can't select the MDI's menu using the MenuItems() which return [].
I can't use the MenuItems() in my MDI application. Any example is very nice Thanks a lot! -- OpenBookProject-开放图书计划邮件列表 详情: http://groups.google.com/group/OpenBookProject 维基: http://wiki.woodpecker.org.cn/ -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
On Wed, 17 Dec 2008 11:52:17 -0800 (PST), Rominsky john.romin...@gmail.com
wrote:
On Dec 17, 10:59 am, Christian Heimes li...@cheimes.de wrote:
Rominsky schrieb:
I am trying to use dir to generate a list of methods, variables, etc.
I would like to be able to go through the list and seperate the
objects by type using the type() command, but the dir command returns
a list of strings. When I ask for the type of an element, the answer
is always string. How do I point at the variables themselves. A
quick example is:
a = 5
b = 2.0
c = 'c'
lst = dir()
for el in lst:
print type(el)
for name, obj in vars().iteritems():
print name, obj
Christian
I do have some understanding of the pythonic methodology of
programming, though by far I still don't consider myself an expert.
The problem at hand is that I am coming from a matlab world and trying
to drag my coworkers with me. I have gotten a lot of them excited
about using python for this work, but the biggest gripe everytime is
they want their matlab ide. I am trying to experiment with making
similar pieces of the ide, in particular I am working on the workspace
window which lists all the current variables in the namespace, along
with their type, size, value, etc I am trying to create a python
equivalent. I can get dir to list all the variables names in a list
of strings, but I am trying to get more info them. hence the desire
to do a type command on them. I like the locals and globals commands,
but I am still trying to get more info. I have started using the eval
command with the strings, which is working, but I am curious if there
is a better or more elegant way of getting the info. The eval example
would be something like:
a = 5
b = 2.0
c = 'c'
lst = dir()
for el in lst:
print el + '\t' + str(eval('type(%s)'%el))
It works, now I am curious if there is a better way.
What about this:
for name, obj in vars().iteritems():
print name, obj
Christian
Jean-Paul
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[ANN] EuroPython 2009 – Call for Partic ipation!
On behalf of the EuroPython 2009 organisation it is my privilege and honour to announce the 'Call for Participation' for EuroPython 2009! EuroPython is the conference for the communities around Python, including the Django, Zope and Plone communities. This year's conference will be held in Birmingham, UK from Monday 29th June to Saturday 4th July 2009. Talks Themes Do you have something you wish to present at EuroPython? Go to http://www.europython.eu/talks/cfp/ for this year's themes and submissions criteria, the deadline is on 5th April 2009. Other Talks, Activities and Events Have you got something which does not fit the above? Visit http://www.europython.eu/talks/ . Help Us Out We could use a hand any contribution is welcome, please take a look at http://www.europython.eu/contact/ . Sponsors An unique opportunity to affiliate with the prestigious EuroPython conference! http://www.europython.eu/sponsors/ Spread the Word Improve our publicity by distributing this announcement in your corner of the community, please coordinate this with the organizers: http://www.europython.eu/contact/ General Information For more information about the conference, please visit http://www.europython.eu/ Looking forward to see you! The EuroPython Team -- http://mail.python.org/mailman/listinfo/python-list
Re: mysql hash generator in python
Hi Matias.
Could you show us the 'class implementation'?
Whether class or not the result should be the same.
If it isn't, then there should be a small error.
If we have both code versions to look at it's easier to help you.
bye
N
Matías Hernández wrote:
(sorry for my english, but i'm speak spanish)
Hi list.. this is my first post... and obviously if for help..
I try to implement the password function of mysql in a python script.
I read that the password function of mysql was implemented with a double
sha1()
I python i try this:
example1:
if __name__==__main__:
s = hashlib.sha1()
s.update('test')
s2 = hashlib.sha1()
s2.update(s.digest()
print s2.hexdigest()
This script show me the same hash that password function of mysql, but
when i implement this in a class the hash is different??? why???
And if is posible??? can you show a example code of old_password
function of mysql in python???
THNX
--
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Re: Need help improving number guessing game
D'Arcy J.M. Cain da...@druid.net writes: On Tue, 16 Dec 2008 13:59:24 -0800 Scott David Daniels scott.dani...@acm.org wrote: def yesno(s): s = s.strip().lower() if not s in (y, n): There was a thread about is not recently. Python also allows not in. if s not in (y, n): You could also do this to be a little more user friendly: if not (s and s[0] in (y, n)): Or: if s[:1] not in (y, n): -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
Why no lexical scoping for a method within a class?
Quoth walterbyrd walterb...@iname.com: For a language as well structured as Python, this seems somewhat sloppy, and inconsistant. Or is there some good reason for this? Yes. It's called Object Oriented Programming. Here is what I mean: def a(): x = 99 print x def b(): print x a() b() # raises an exception because x is not defined. However in the methods are within a class, the scoping seems to work differently. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() i.a() i.b() # this works, why no lexical scoping? Because x is an attribute. If you don't understand what that means, read any introductory article on OOP. To give you a clue, if you had said: class ab(): def a(self): x = 99 print x def b(self): print x You'd have gotten the exception you expected (assuming x wasn't defined globally). --RDM -- http://mail.python.org/mailman/listinfo/python-list
Why no lexical scoping for a method within a class?
For a language as well structured as Python, this seems somewhat sloppy, and inconsistant. Or is there some good reason for this? Here is what I mean: def a(): x = 99 print x def b(): print x a() b() # raises an exception because x is not defined. However in the methods are within a class, the scoping seems to work differently. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() i.a() i.b() # this works, why no lexical scoping? -- http://mail.python.org/mailman/listinfo/python-list
Re: Python, XML and XPath
Hole h0lefor...@gmail.com ha scritto nel messaggio news:daf5cd00-36dc-4ab4-976e-a6d859b52...@w24g2000prd.googlegroups.com... Hi all, I hope this is not an overasked question but I find myself quite confused about python xml management (I have to use python for a project and I come from java world, you know...where frameworks, libraries and tools to use are standard de iure or standard de facto). I need to use XML parsing with xpath: a simple xml reader. You can try lxml, have a look here http://codespeak.net/lxml/xpathxslt.html I've found that the standard distribution of python doesn't include xpath support modules so I've decided to add libxml2. I've installed cygwin c compiler but I still have errors like the following: C:\Python25\Lib\libxml2-python-2.6.9python setup.py build install I never used libxml2 but version 2.6.9 seems quite old, according to this page: http://users.skynet.be/sbi/libxml-python/ Bye, Enrico -- http://mail.python.org/mailman/listinfo/python-list
Re: Selecting a different superclass
On Wed, Dec 17, 2008 at 6:41 AM, psaff...@googlemail.com psaff...@googlemail.com wrote: This might be a pure OO question, but I'm doing it in Python so I'll ask here. snip The problem is that IDPointSet and MicroArrayPointSet will need to inherit from PointSet or TraceablePointSet based on whether I'm handling traceable points or not. Can I select a superclass conditionally like this in Python? Am I trying to do something really evil here? You're doing something really dynamic; don't think I'd call it inherently evil though. All you have to do is use a variable in the inheritance syntax, it's really quite simple: superclass = TraceablePointSet if tracing else PointSet class IDPointSet(superclass): #body code here #use same trick for MicroArrayPointSet Cheers, Chris -- Follow the path of the Iguana... http://rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: regex problem ..
Analog Kid wrote: Hi guys: Thanks for your responses. Points taken. Basically, I am looking for a combination of the following ... [^\w] and %(?!20) ... How do I do this in a single RE? Thanks for all you help. Regards, AK On Mon, Dec 15, 2008 at 10:54 PM, Steve Holden st...@holdenweb.com mailto:st...@holdenweb.com wrote: Analog Kid wrote: Hi All: I am new to regular expressions in general, and not just re in python. So, apologies if you find my question stupid :) I need some help with forming a regex. Here is my scenario ... I have strings coming in from a list, each of which I want to check against a regular expression and see whether or not it qualifies. By that I mean I have a certain set of characters that are permissible and if the string has characters which are not permissible, I need to flag that string ... here is a snip ... flagged = list() strs = ['HELLO', 'Hi%20There', '123...@#@'] p = re.compile(r[^a-zA-Z0-9], re.UNICODE) for s in strs: if len(p.findall(s)) 0: flagged.append(s) print flagged my question is ... if I wanted to allow '%20' but not '%', how would my current regex (r[^a-zA-Z0-9]) be modified? The essence of the approach is to observe that each element is a sequence of zero or more character, where character is either letter/digit or escape. So you would use a pattern like ([a-zA-Z0-9]|%[0-9a-f][0-9a-f])+ Did you *try* the above pattern? regards Steve -- Steve Holden+1 571 484 6266 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Free place to host python files?
James Mills wrote: On Wed, Dec 17, 2008 at 10:25 AM, Chris Rebert c...@rebertia.com wrote: I'll plug Bitbucket (http://bitbucket.org/). It gives you 150MB of Mercurial hosting for free, along with a bug tracker and wiki. And I hear it's implemented using Django. FreeHG (http://freehg.org) is pretty good too :) cheers James I'll throw in https://launchpad.net/ too. No wiki, though. And http://github.com/, I guess. -- -- http://mail.python.org/mailman/listinfo/python-list
Re: Transferring a file over sockets
On Wed, 17 Dec 2008 17:41:46 +0530, Ferdinand Sousa ferdinandso...@gmail.com
wrote:
I am using sockets to transfer a file over LAN. There are 2 scripts, the
server opens a listens for connection and the client is run on another
machine. I always make sure the server is run first. The strange thing is
that if the the server script is double-clicked and executed (run in a
console with title %Python path%python.exe) the output file saved on the
server is truncated. It works just fine if you open the server script in
IDLE and then run it. The client script can be run in either way, it still
works. You could try using any arbitrary file to test this behaviour after
changing the file name in both the scripts.
==
# file receiver
# work in progress
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
HOST = '192.168.1.17'
PORT = 31400
s.bind((HOST, PORT))
s.listen(3)
conn, addr = s.accept()
print 'conn at address',addr
conn.send('READY')
f = open('C:\\Documents and Settings\\USER\\Desktop\\test.pdf','wb')
fsize=int(conn.recv(8))
print 'File size',fsize
f.write(conn.recv(fsize))
f.close()
conn.close()
s.close()
raw_input('Press any key to exit')
===
# file sender !!!
# Work in progress
import socket, os
from stat import ST_SIZE
HOST = '192.168.1.17'
PORT = 31400 # Arbitrary non-privileged port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST,PORT))
if s.recv(5)!='READY':
raw_input('Unable to connect \n\n Press any key to exit ...')
s.close()
exit()
f=open('C:\\Documents and Settings\\USER\\Desktop\\t.pdf', 'rb')
fsize=os.stat(f.name)[ST_SIZE]
s.send(str(fsize))
s.send(f.read())
s.close()
f.close()
===
Thanks for reading!!
You're not handling your sockets properly. send() does not necessary
send the entire string you pass to it. recv(n) does not necessarily
return an n-length string. Read the socket documentation more carefully
and try fixing those issues. Or try using Twisted which presents a
somewhat easier API to use.
Jean-Paul
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Re: help I'm getting delimited
Quoth John Machin sjmac...@lexicon.net: On Dec 18, 1:28 am, aka alexoploca...@gmail.com wrote: @expose(allow_json=True) Means what? Does what? Does the problem still happen without that? Means what he's posting is not a standalone script :) He says it's part of his turbogears ap. @expose says that this method is callable by name from a URL, and allow_json means it can be called with a parameter requesting a json formatted response instead of html. Funny, the indentation changed there --- for the very last time, is that the actual code of a standalone script that reproduces the problem? Alex, I would strongly suggest that you move your code out into a standalone script and debug it there (you'll get more help from this group if you do, for one thing!). After you get it working standalone you can incorporate it back into your Turbogears ap. --RDM -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Dec 17, 10:19 am, walterbyrd walterb...@iname.com wrote: For a language as well structured as Python, this seems somewhat sloppy, and inconsistant. Or is there some good reason for this? Here is what I mean: def a(): x = 99 print x def b(): print x a() b() # raises an exception because x is not defined. However in the methods are within a class, the scoping seems to work differently. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() i.a() i.b() # this works, why no lexical scoping? If scoping worked as you want, how, pray tell, would you define object attributes? -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
On Dec 18, 1:28 am, aka alexoploca...@gmail.com wrote:
Hi John, thanks.
You're right, I didn't past the method header because I thought it
didn't matter when the input filename is hardcoded.
The try/except isn't very helpful indeed so I commented it out.
You're right I wrongly referred to the UnicodeReader
class in my first post because that's ultimately where I want to go
so
I outcommented it here for you to see.
The fact is that neither csv.reader nor the UnicodeReader will read
the file, while writing with the UnicodeWriter
works like a charm.
That's why I put str() around roles to see any content.
I simplified the csv-file by cutting off columns without result. The
file looks now like:
id;company;department
12;Cadillac;Research
11;Ford;Accounting
10;Chrysler;Sales
The dictionary on the return is because this code is part of my
TurboGears application.
The entire method is:
import csv
from utilities.urw import UnicodeWriter, UnicodeReader
Pardon my ignorance, but what is utilities.urw??
@expose(allow_json=True)
Means what? Does what?
Does the problem still happen without that?
Funny, the indentation changed there --- for the very last time, is
that the actual code of a standalone script that reproduces the
problem?
def import_roles(self, input=None, *args, **kwargs):
inp = 'C:/temp/test.csv'
roles = []
msg = ''
## try:
fp = open(inp, 'rb')
reader = csv.reader(fp, dialect='excel', delimiter=';')
## reader = UnicodeReader(fp, dialect='excel', delimiter=';')
for r in reader:
roles.append(r[0])
fp.close()
## except:
## msg = Something's wrong with the csv.reader
return dict(filepath=inp,
roles=str(roles),
msg=msg)
csv.reader results in: for r in reader: Error: line contains NULL
byte
Looks like the file is stuffed. Have you tried inspecting it with a
tool that would actually show a '\x00' or a '\xff' unambiguously? If
you don't have a fancy one, use the Python interactive prompt:
open('your_file.csv', 'rb').read()
Use of UnicodeReader results in: UnicodeDecodeError: 'utf8' codec
can't decode byte 0xff in position 0: unexpected code byte
Will post only complete code from now on thanks.
Just make sure it's runnable and it's what you actually ran thanks.
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something else instead of PIL?
Hi what has happened to PIL? No updates since two years. Or does one know an alternative lib for resizing images? cheers Reimar -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
walterbyrd wrote: For a language as well structured as Python, this seems somewhat sloppy, and inconsistant. Or is there some good reason for this? Here is what I mean: def a(): x = 99 print x def b(): print x a() b() # raises an exception because x is not defined. However in the methods are within a class, the scoping seems to work differently. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() i.a() i.b() # this works, why no lexical scoping? Because what you do is to create instance variables. Why do you expect them not working if you explicitly access them? The real analog of your example would be this: class ab(): def a(self): x = 100 print x def b(self): print x which provokes the same error. however, there *are* different scoping rules, classes don't create a lexical scope for their own variables: class foo(object): x = 100 def a(self): print x Diez -- http://mail.python.org/mailman/listinfo/python-list
Python, XML and XPath
Hi all, I hope this is not an overasked question but I find myself quite confused about python xml management (I have to use python for a project and I come from java world, you know...where frameworks, libraries and tools to use are standard de iure or standard de facto). I need to use XML parsing with xpath: a simple xml reader. I've found that the standard distribution of python doesn't include xpath support modules so I've decided to add libxml2. I've installed cygwin c compiler but I still have errors like the following: C:\Python25\Lib\libxml2-python-2.6.9python setup.py build install C:\Python25\lib\distutils\dist.py:247: UserWarning: 'licence' distribution option is deprecated; use 'license' warnings.warn(msg) running build running build_py running build_ext building 'libxml2mod' extension writing build\temp.win32-2.5\Release\libxml2mod.def C:\MinGW\bin\gcc.exe -mno-cygwin -shared -s build \temp.win32-2.5\Release\libxml2-py.o build\temp.win32-2.5\Release \libxml.o build\temp.win32-2.5\Release\types.o build \temp.win32-2.5\Release\libxml2mod .def -L/usr\lib -LC:\Python25\libs -LC:\Python25\PCBuild -llibxslt - llibexslt -llibxml2 -lpython25 -lmsvcr71 -o build \lib.win32-2.5\libxmlmods\libxml2mod.pyd build\temp.win32-2.5\Release\libxml2-py.o:libxml2-py.c:(.text+0x1629): undefined reference to `_imp__xmlFree' build\temp.win32-2.5\Release\libxml2-py.o:libxml2-py.c:(.text+0x2802): undefined reference to `_imp__xmlFree' build\temp.win32-2.5\Release\libxml2-py.o:libxml2-py.c:(.text+0x44b2): undefined reference to `_imp__xmlFree' build\temp.win32-2.5\Release\libxml2-py.o:libxml2-py.c:(.text+0x50e4): undefined reference to `_imp__xmlFree' build\temp.win32-2.5\Release\libxml2-py.o:libxml2-py.c:(.text+0x5519): undefined reference to `_imp__xmlFree' build\temp.win32-2.5\Release\libxml2-py.o:libxml2-py.c:(.text+0x7339): more undefined references to `_imp__xmlFree' follow Does anyone know how to solve this issue or has suggestions for another (easy-to-install) xml-xpath library? Thanks for your support! -- http://mail.python.org/mailman/listinfo/python-list
Re: something else instead of PIL?
Reimar Hi what has happened to PIL? No updates since two years. It's well-written, stable code. As far as I know it does what people want (at least it's done everything I've needed when I've used it). Why should it matter that there hasn't been an official release in two years? -- Skip Montanaro - s...@pobox.com - http://smontanaro.dyndns.org/ -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess.Popen inheriting
Aaron Brady wrote: I thought so too. The web seems to say that on Linux they are, and on Windows, you need to call DuplicateHandle for it. I hit this problem - it looks like pipes aren't very versatile on Windows. There's also the complicating factor that the handles in windows aren't the same as the file numbers that Python uses, so you have to convert between them. It would be nice if Python created pipes that are properly inheritable by default by child processes, as they're mostly used for IPC. It was so painful that I converted my code to use sockets instead, which seem much more portable between Windows and Unix (though you don't get to use socketpair and AF_UNIX in Windows). Jeremy -- Jeremy Sanders http://www.jeremysanders.net/ -- http://mail.python.org/mailman/listinfo/python-list
Transferring a file over sockets
I am using sockets to transfer a file over LAN. There are 2 scripts, the
server opens a listens for connection and the client is run on another
machine. I always make sure the server is run first. The strange thing is
that if the the server script is double-clicked and executed (run in a
console with title %Python path%python.exe) the output file saved on the
server is truncated. It works just fine if you open the server script in
IDLE and then run it. The client script can be run in either way, it still
works. You could try using any arbitrary file to test this behaviour after
changing the file name in both the scripts.
==
# file receiver
# work in progress
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
HOST = '192.168.1.17'
PORT = 31400
s.bind((HOST, PORT))
s.listen(3)
conn, addr = s.accept()
print 'conn at address',addr
conn.send('READY')
f = open('C:\\Documents and Settings\\USER\\Desktop\\test.pdf','wb')
fsize=int(conn.recv(8))
print 'File size',fsize
f.write(conn.recv(fsize))
f.close()
conn.close()
s.close()
raw_input('Press any key to exit')
===
# file sender !!!
# Work in progress
import socket, os
from stat import ST_SIZE
HOST = '192.168.1.17'
PORT = 31400 # Arbitrary non-privileged port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST,PORT))
if s.recv(5)!='READY':
raw_input('Unable to connect \n\n Press any key to exit ...')
s.close()
exit()
f=open('C:\\Documents and Settings\\USER\\Desktop\\t.pdf', 'rb')
fsize=os.stat(f.name)[ST_SIZE]
s.send(str(fsize))
s.send(f.read())
s.close()
f.close()
===
Thanks for reading!!
Best regards,
Ferdi
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Re: something else instead of PIL?
On Wed, Dec 17, 2008 at 12:48 PM, Reimar Bauer r.ba...@fz-juelich.de wrote: Hi what has happened to PIL? No updates since two years. The Python Imaging Library is still current; I guess they just haven't found any new bugs or seen fit to add new functionality in a while, though I presume they'll start working on a Python 3.0 port eventually. If you don't like PIL, there's always the (much less popular) Python bindings to ImageMagick: http://www.imagemagick.org/script/api.php#python Cheers, Chris -- Follow the path of the Iguana... http://rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
Re: regex problem ..
Hi guys: Thanks for your responses. Points taken. Basically, I am looking for a combination of the following ... [^\w] and %(?!20) ... How do I do this in a single RE? Thanks for all you help. Regards, AK On Mon, Dec 15, 2008 at 10:54 PM, Steve Holden st...@holdenweb.com wrote: Analog Kid wrote: Hi All: I am new to regular expressions in general, and not just re in python. So, apologies if you find my question stupid :) I need some help with forming a regex. Here is my scenario ... I have strings coming in from a list, each of which I want to check against a regular expression and see whether or not it qualifies. By that I mean I have a certain set of characters that are permissible and if the string has characters which are not permissible, I need to flag that string ... here is a snip ... flagged = list() strs = ['HELLO', 'Hi%20There', '123...@#@'] p = re.compile(r[^a-zA-Z0-9], re.UNICODE) for s in strs: if len(p.findall(s)) 0: flagged.append(s) print flagged my question is ... if I wanted to allow '%20' but not '%', how would my current regex (r[^a-zA-Z0-9]) be modified? The essence of the approach is to observe that each element is a sequence of zero or more character, where character is either letter/digit or escape. So you would use a pattern like ([a-zA-Z0-9]|%[0-9a-f][0-9a-f])+ regards Steve -- Steve Holden+1 571 484 6266 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: something else instead of PIL?
what has happened to PIL? No updates since two years. The Python Imaging Library is still current; I guess they just haven't found any new bugs or seen fit to add new functionality in a while, though I presume they'll start working on a Python 3.0 port eventually. That's actually an interesting question. Does anybody know if PIL is being ported to 3.0? Are there such plans? Maybe even code? Cheers, Daniel -- Psss, psss, put it down! - http://www.cafepress.com/putitdown -- http://mail.python.org/mailman/listinfo/python-list
Selecting a different superclass
This might be a pure OO question, but I'm doing it in Python so I'll ask here. I'm writing a number crunching bioinformatics application. Read lots of numbers from files; merge, median and munge; draw plots. I've found that the most critical part of this work is validation and traceability - where does this final value come from? How has it been combined with other values? Is that right? My current implementation stores all my values just as floats with a class called PointSet for storing one set of such values, with various mathematical and statistical methods. There are several subclasses of PointSet (IDPointSet, MicroArrayPointSet) for obtaining values from different file types and with different processing pipelines. I'm planning to instead store each value in a TraceablePoint class which has members that describe the processing stages this value has undergone and a TraceablePointSet class to store groups of these - this will contain all the same methods as PointSet, but will operate on TraceablePoints instead of floats. Of course, this will be much slower than just floats, so I'd like to be able to switch it on and off. The problem is that IDPointSet and MicroArrayPointSet will need to inherit from PointSet or TraceablePointSet based on whether I'm handling traceable points or not. Can I select a superclass conditionally like this in Python? Am I trying to do something really evil here? Any other bright ideas on my application also welcome. Peter -- http://mail.python.org/mailman/listinfo/python-list
getting object instead of string from dir()
I am trying to use dir to generate a list of methods, variables, etc. I would like to be able to go through the list and seperate the objects by type using the type() command, but the dir command returns a list of strings. When I ask for the type of an element, the answer is always string. How do I point at the variables themselves. A quick example is: a = 5 b = 2.0 c = 'c' lst = dir() for el in lst: print type(el) Right now I am understandably getting all types being output as strings, how do i get the type of the actual objects returned from dir ()? -- http://mail.python.org/mailman/listinfo/python-list
Re: weird dict problem, how can this even happen?
Steven D'Aprano wrote: On Tue, 16 Dec 2008 14:32:39 +0100, Joel Hedlund wrote: Duncan Booth wrote: Alternatively give up on defining hash and __eq__ for FragmentInfo and rely on object identity instead. Object identity wouldn't work so well for caching. Objects would always be drawn as they appeared for the first time. No updates would be shown until the objects were flushed from the cache. Perhaps I don't understand your program structure, but I don't see how that follows. First off, please note that I consider my problem to be solved, many thanks to c.l.p and especially Duncan Booth. But of course continued discussion on this topic can be both enlightening and entertaining as long as people are interested. So here goes: I'm making a scientific program that visualizes data. It can be thought of as a freely zoomable map viewer with a configurable stack of data feature renderers, themselves also configurable to enhance different aspects of the individual features. As you zoom in, it becomes possible to render more types of features in a visually recognizable manner, so consequentially more feature renderers become enabled. The determining properties for the final image are then the coordinates and zoom level of the view, and the current renderer stack configuration. Rendering may be time consuming, so I cache the resulting bitmap fragments using a key object called FragmentInfo that holds this information. Some renderers may take a very long time to do their work, so in order to keep the gui nice and responsive, I interrupt the rendering chain at that point, put the remainder of the rendering chain in a job pool, and postpone finishing up the rendering until there are cpu cycles to spare. At that time, I go through the job pool and ask the cache which fragment was most recently accessed. This fragment is the most likely to actually be in the current view, and thus the most interesting for the user to have finallized. Now, when the user navigates the view to any given point, the gui asks the cache if the bitmap fragments necessary to tile up the current view have already been rendered, and if so, retrieves them straight from the cache and paints them to the screen. And that's why object identity wouldn't work. If the user changes something in the config for the current renderer stack (=mutates the objects), the renderers still retain the same object identities and therefore the old versions would be retrieved from the cache, and no updates would be shown until the fragments are flushed from the cache, and the fragment subsequently redrawn. I guess you could delve deep into the data members and pull out all their object identities and hash wrt that if you'd really want to, but I don't really see the point. The stupid cache implementation that I originally employed used a dict to store the FragmentInfo:BitmapFragment items plus a use tracker (list) on the side. This obviously doesn't work, because as soon as the renderer stack mutates, list and dict go out of sync and I can no longer selectively flush old items from the dict, because it's not readily apparent how to reconstruct the old keys. Purely using lists here is vastly superior because I can just .pop() the least recently used items from the tail and be done with them. Also for lists as small as this, the cost in performance is at most negligible. I've been experimenting with a list cache now and I can't say I'm noticing any change in performance for a cache of 100 items. 100 items isn't very big though. If you have 50,000 items you may notice significant slow down :) If having many items in the cache is possible, you should consider using a binary search instead of a linear search through the cache. See the bisect module. Thanks for the tip, but I don't forsee this cache ever needing to be that big. ~100 is quite enough for keeping the gui reasonably responsive in this case. /Joel -- http://mail.python.org/mailman/listinfo/python-list
Re: help I'm getting delimited
Due to being in a hurry I didn't paste correctly so I lost the try clause (sorry). The intention is to parse a csv file and (ultimately) put values of column 1 (id) in a list (so I need to append in the loop) that will be used to fill a session var. The complete code is: roles = [] inp = 'C:/temp/test.csv' try: fp = open(inp, 'rb') reader = csv.reader(fp, dialect='excel', delimiter=';') for r in reader: roles.append(r) ## ultimately should be something like r.id or r[0] except: msg = 'Something's wrong with the csv.reader' return dict(file=inp,roles=str(roles)) The roles list isn't populated at all :( -- http://mail.python.org/mailman/listinfo/python-list
OT: Binary tree logarithms properties
Hi, I'm searching for a clear explanation of binary tree properties, expecially the ones related to logarithms. For example, I know that in a tree with 2n-1 nodes, we have log(n) levels, from 0 to log(n). So, if k is the level, the nodes on a level have indexes between 2^k and 2^(k+1)-1. For k=0 we have 2 and 3. For k=1 we have 4, 5, 6, 7 and so on. I know this after I studied some exercises on my book. Anyway there is no explanation or demonstration of these properties. I know this is not the better place to ask (or maybe it is?), but maybe someone can point me to something useful. Thanks, bye -- http://mail.python.org/mailman/listinfo/python-list
Re: WinMerge--B/W Shading of Printed Copy to Show Differences?
W. eWatson wrote: Jason Scheirer wrote: On Dec 16, 3:56 pm, W. eWatson notval...@sbcglobal.net wrote: Is there a way to highlight differences between the two files when printing in b/w? Help suggests there may be some texturing, but all I see is color choices. -- W. eWatson (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time) Obz Site: 39° 15' 7 N, 121° 2' 32 W, 2700 feet Web Page: www.speckledwithstars.net/ WinMerge is written in C++ and not even remotely related to Python. Well, yes, but it has applicability to Python (and maybe other languages) in that I can use it to find differences between two sets of code. If not here, where? comp.lang.??? ? Hmm, I guess no one here uses it. I did find a winmerge mailing list, so will work it out there. -- W. eWatson (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time) Obz Site: 39° 15' 7 N, 121° 2' 32 W, 2700 feet Web Page: www.speckledwithstars.net/ -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
On Wed, Dec 17, 2008 at 1:52 PM, Rominsky john.romin...@gmail.com wrote: On Dec 17, 10:59 am, Christian Heimes li...@cheimes.de wrote: Rominsky schrieb: I am trying to use dir to generate a list of methods, variables, etc. I would like to be able to go through the list and seperate the objects by type using the type() command, but the dir command returns a list of strings. When I ask for the type of an element, the answer is always string. How do I point at the variables themselves. A quick example is: a = 5 b = 2.0 c = 'c' lst = dir() for el in lst: print type(el) for name, obj in vars().iteritems(): print name, obj Christian I do have some understanding of the pythonic methodology of programming, though by far I still don't consider myself an expert. The problem at hand is that I am coming from a matlab world and trying to drag my coworkers with me. I have gotten a lot of them excited about using python for this work, but the biggest gripe everytime is they want their matlab ide. I am trying to experiment with making similar pieces of the ide, in particular I am working on the workspace window which lists all the current variables in the namespace, along with their type, size, value, etc I am trying to create a python equivalent. I can get dir to list all the variables names in a list of strings, but I am trying to get more info them. hence the desire Are you familiar with the ipython console? http://ipython.scipy.org/moin/ It is quite powerful; in particular, the %who and %whos 'magic functions' will do much of what you'd like: [501]$ ipython Python 2.5.2 (r252:60911, Jul 31 2008, 17:31:22) Type copyright, credits or license for more information. IPython 0.8.1 -- An enhanced Interactive Python. ? - Introduction to IPython's features. %magic - Information about IPython's 'magic' % functions. help- Python's own help system. object? - Details about 'object'. ?object also works, ?? prints more. In [1]: a = 'foo' In [2]: b = 'bar' In [3]: c = 5.234 In [4]: import os In [5]: d = os In [6]: whos Variable Type Data/Info -- a str foo b str bar c float 5.234 d modulemodule 'os' from '/usr/lib/python2.5/os.pyc' os modulemodule 'os' from '/usr/lib/python2.5/os.pyc' In [7]: import numpy as np In [8]: aa = np.zeros(100) In [9]: whos Variable Type Data/Info --- a strfoo aa ndarray100: 100 elems, type `float64`, 800 bytes b strbar c float 5.234 d module module 'os' from '/usr/lib/python2.5/os.pyc' np module module 'numpy' from '/us...ages/numpy/__init__.pyc' os module module 'os' from '/usr/lib/python2.5/os.pyc' And I trust you've heard of numpy, scipy and matplotlib? http://www.scipy.org/ http://matplotlib.sourceforge.net/ http://numpy.scipy.org/ Cheers, Kurt -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
walterbyrd a écrit : On Dec 17, 8:41 am, prueba...@latinmail.com wrote: If scoping worked as you want, how, pray tell, would you define object attributes?- Hide quoted text - I suppose you could do this: class className(): varname = whatever This defines a class attribute - that is, an attribute of the className class object, accessible either thru the className object or it's instances if not shadowed by an instance attribute by the same name/ def fname(self, varname): . . . . Instead of having variable defined within methods to be global everywhere within the class. There's nothing like a variable defined within (a) method, because you never define methods in Python - only functions. So there's no difference in scoping rules for functions defined within a class statement block or outside a class statement block. Anyway, it's not a matter of what I like, I am just trying to understand the reason behind the scoping rules. Then you should start with understanding the scoping rules. -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
walterbyrd a écrit : On Dec 17, 9:04 am, rdmur...@bitdance.com wrote: Yes. It's called Object Oriented Programming. I think you mean it's *Python* Object Oriented Programming. I am not sure that every other OO language works like that. Every OO languages having such a thing as a global variable makes a distinction between an instance attributes and a global variable. Your problem is that you are confusing variables and attributes. In Python, 'anything.anyname' (note the dot) is the attribute 'anyname' of object 'anything'. -- http://mail.python.org/mailman/listinfo/python-list
Location HTTP Header
Hi all. I tried this stupid script on my server: #! /usr/bin/env python print 'Location: http://www.google.com\n' and it didn't work, I get a blank page. I first tried the Location header in another script, and when execution got to that point, it would just sort of ignore it, because the script would keep running to the end of the code (or stop at some unhandled exception). I ran chmod 755 script.cgi and the cgi script is at the correct directory, but still nothing. I think it might be an error from the server (the old PythonWeb.org webserver), maybe it doesn't support Location? Is that even possible? Or maybe there's some setup I forgot to do? Any ideas? Thanks a lot. -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess.Popen inheriting
En Wed, 17 Dec 2008 12:21:38 -0200, Jeremy Sanders jeremy+complangpyt...@jeremysanders.net escribió: Aaron Brady wrote: I thought so too. The web seems to say that on Linux they are, and on Windows, you need to call DuplicateHandle for it. Or set bInheritHandle=True when creating the pipe initially. os.pipe() doesn't do that. I hit this problem - it looks like pipes aren't very versatile on Windows. There's also the complicating factor that the handles in windows aren't the same as the file numbers that Python uses, so you have to convert between them. It would be nice if Python created pipes that are properly inheritable by default by child processes, as they're mostly used for IPC. I'd say it is a bug in os.pipe implementation; they should be inheritable by default, as in posix (after all, the code is in posixmodule.c). -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: The rule of literal string
But what repr() do remain a black hole! Han -- http://mail.python.org/mailman/listinfo/python-list
C API and memory allocation
Hi
I'm slightly confused about some memory allocations in the C API.
Take the first example in the documentation:
static PyObject *
spam_system(PyObject *self, PyObject *args)
{
const char *command;
int sts;
if (!PyArg_ParseTuple(args, s, command))
return NULL;
sts = system(command);
return Py_BuildValue(i, sts);
}
What I'm confused about is the memory usage of command. As far as I
understand the compiler provides space for the size of the pointer, as
sizeof(command) would indicate. So I'm assuming PyArg_ParseTuple()
must allocate new memory for the returned string. However there is
nothing in the API that provides for freeing that allocated memory
again. So does this application leak memory then? Or am I
misunderstanding something fundamental?
Regards
Floris
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Re: help I'm getting delimited
On Dec 18, 3:15 am, aka alexoploca...@gmail.com wrote:
John, this is the actual code I ran in TurboGears which is a Python
framework.
It's not complete -- the change in indentation would have caused a
SyntaxError.
If (as you appear to assert) the problem is in the csv module, then
create a small stand-alone no-TurboGears Python script and a test file
which together demonstrate the problem reproducibly so that the
problem can investigated by anyone with a standard TurboGears-free
Python installation.
If you can't reproduce the problem in that manner, then you may need
to seek assistance in a TurboGears-specific forum.
I should have left away the import statements. Trust me, the problem
isn't in there because the UnicodeWriter is functioning perfectly.
Do you mean that this file was created by whatever.UnicodeWriter? If
so, did you just now discover this information?
How do you know that the UnicodeWriter is functioning perfectly?
What does functioning perfectly mean to you? In particular, what
encoding is it using?
I did allready sanitate the csv file to these four lines in Notepad so
there isn't anything more than this:
id;company;department
12;Cadillac;Research
11;Ford;Accounting
10;Chrysler;Sales
Which do you mean:
(a) you typed those lines into Notepad yourself
(b) you took a copy of a file created by whatever.UnicodeWriter,
opened it with Notepad, trimmed off some rows and columns, and saved
it again
?
You said earlier
csv.reader results in: for r in reader: Error: line contains NULL
byte
Use of UnicodeReader results in: UnicodeDecodeError: 'utf8' codec
can't decode byte 0xff in position 0: unexpected code byte
Those results are consistent with your file being encoded in utf16_le,
with the utf16_le BOM ('\xff\xfe') at the start of the file.
Have you, as I asked, looked at the file with some better-than-Notepad
diagnostic apparatus?
Here's a likely hypothesis: the file was written in utf16. In that
case:
either (i) you really want utf16 (why?), so:
(1) the csv module will not cope with it, and is not expected to cope
with it
(2) the whatever.UnicodeReader should (in order of preference):
(a) be allowed to find out for itself that 'utf16' is the go
(b) be told explicitly that 'utf16' is the go
(c) be served with a bug report
OR (ii) you really want utf8, so:
(1) the csv module should be happy
(2) the whatever.UnicodeWriter should be told to use 'utf8'
(3) the whatever.UnicodeReader should (in order of preference):
[as above but s/16/8/]
HTH,
John
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Re: The rule of literal string
Li Han wrote:
But what repr() do remain a black hole!
Han
Try: print repr(repr('))
that might enlighten you.
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Re: The rule of literal string
On 12月18日, 上午7时12分, Scott David Daniels scott.dani...@acm.org wrote:
Scott wrote:
Try: print repr(repr('))
that might enlighten you.
I found that print( repr( repr( arbitarystring ) ) ) == repr
( arbitarystring )
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Re: The rule of literal string
2008/12/17 Li Han lihang9...@gmail.com:
On 12月18日, 上午7时12分, Scott David Daniels scott.dani...@acm.org wrote:
Scott wrote:
Try: print repr(repr('))
that might enlighten you.
I found that print( repr( repr( arbitarystring ) ) ) == repr
( arbitarystring )
As I stated previously, the key rule is:
eval(repr(something)) == something
That is, repr() gives a string of Python code that, when evaluated,
results in what you gave to repr().
So repr('') == ''
And repr('') == \''\
Which when print()-ed is: ''
And eval('') is the same as entering two apostrophes ('') at the
REPL, both of which give an empty string object.
Cheers,
Chris
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Re: The rule of literal string
On Thu, Dec 18, 2008 at 9:25 AM, Chris Rebert c...@rebertia.com wrote:
As I stated previously, the key rule is:
eval(repr(something)) == something
This rule is only true for basic data types;
For example:
eval(repr(1)) == 1
True
eval(repr([1, 2, 3])) == [1, 2, 3]
True
eval(repr({a: 1, b: 2, c: 3})) == {a: 1, b: 2, c: 3}
True
eval(repr(foo)) == foo
True
I guess the key thing here is that the repr
implementation (__repr__) for str, int, float
list and dict return sensible represenations
that Python _can_ evaluate with eval(...)
--JamesMills
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Re: C API and memory allocation
Hello again On Dec 17, 11:06 pm, Floris Bruynooghe floris.bruynoo...@gmail.com wrote: So I'm assuming PyArg_ParseTuple() must allocate new memory for the returned string. However there is nothing in the API that provides for freeing that allocated memory again. I've dug a little deeper into this and found that PyArg_ParseTuple (and friends) end up using PyString_AS_STRING() (Python/getargs.c:793) which according to the documentation returns a pointer to the internal buffer of the string and not a copy and that because of this you should not attempt to free this buffer. But how can python now know how long to keep that buffer object in memory for? When the reference count of the string object goes to zero the object can be deallocated I though, and then your pointer will point to something different all of a sudden. Does this mean you always have too keep a reference to the original objects when you've extracted information from them with PyArg_Parse*() functions? (At least while you want to hang on to that information.) Regards Floris -- http://mail.python.org/mailman/listinfo/python-list
Re: The rule of literal string
On Wed, Dec 17, 2008 at 3:34 PM, James Mills
prolo...@shortcircuit.net.au wrote:
On Thu, Dec 18, 2008 at 9:25 AM, Chris Rebert c...@rebertia.com wrote:
As I stated previously, the key rule is:
eval(repr(something)) == something
This rule is only true for basic data types;
For example:
eval(repr(1)) == 1
True
eval(repr([1, 2, 3])) == [1, 2, 3]
True
eval(repr({a: 1, b: 2, c: 3})) == {a: 1, b: 2, c: 3}
True
eval(repr(foo)) == foo
True
I guess the key thing here is that the repr
implementation (__repr__) for str, int, float
list and dict return sensible represenations
that Python _can_ evaluate with eval(...)
--JamesMills
True, I oversimplified to make things easier to understand. Strictly
speaking, only the basic types make the guarantee I stated. Arbitrary
types can have arbitrary, non-eval()-able repr()s. But the docs do
state eval()-ability as a goal:
repr(object)
Return a string containing a printable representation of an
object. [...] For many types, this function makes an attempt to return
a string that would yield an object with the same value when passed to
eval(), otherwise the representation is a string enclosed in angle
brackets that contains the name of the type of the object together
with additional information often including the name and address of
the object. A class can control what this function returns for its
instances by defining a __repr__() method.
Cheers,
Chris
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Re: Location HTTP Header
En Wed, 17 Dec 2008 20:52:42 -0200, ptn tn.pa...@gmail.com escribió: I tried this stupid script on my server: #! /usr/bin/env python print 'Location: http://www.google.com\n' and it didn't work, I get a blank page. I first tried the Location header in another script, and when execution got to that point, it would just sort of ignore it, because the script would keep running to the end of the code (or stop at some unhandled exception). I assume this is a cgi script. For the Location field to be relevant, the Status should be a 3xx (like 307 Temporary Redirect, or 302 Found) In your case, your server probably has already sent a 200 OK response, so Location is ignored. Try adding a Status line -before Location above- like: print 'Status: 302 Found Any ideas? I'd use a different protocol other than CGI... -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: The rule of literal string
Chris worte:
[snip]
And repr('') == \''\
Which when print()-ed is: ''
And eval('') is the same as entering two apostrophes ('') at the
REPL, both of which give an empty string object.
On my machine:
repr('')
'\'\''
Han
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Re: Why no lexical scoping for a method within a class?
On Wed, 17 Dec 2008 15:19:32 -, walterbyrd walterb...@iname.com wrote: However in the methods are within a class, the scoping seems to work differently. Not really. Hopefully this commentary will show you why. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() This creates |i|, an instance of class |ab|. As yet it is pure and virgin, having nothing but the methods that it gets from |ab|. Soon this will change... i.a() This creates an attribute |x| in |i|, and assigns the number 99 to it. i.b() # this works, why no lexical scoping? This works because you ran |i.a()| first, so |i.x| exists and can be printed out. Lexical scoping is going on here, you're just mistaking what's being scoped; it's the |self| in |b|, which is in scope because it's a parameter. This particular |self| (the |i| you made earlier) happens to have an attribute |x|, so it all works. If however you'd written: j = ab() j.b() then Python would whinge mightily at you, claiming that it knoweth naught of this |x| attribute of which you speak, and can it go home now for this is a silly place. The |self| in |b| is still in lexical scope, though. -- Rhodri James *-* Wildebeeste Herder to the Masses -- http://mail.python.org/mailman/listinfo/python-list
Re: The rule of literal string
On Wed, Dec 17, 2008 at 3:52 PM, Li Han lihang9...@gmail.com wrote:
Chris worte:
[snip]
And repr('') == \''\
Which when print()-ed is: ''
And eval('') is the same as entering two apostrophes ('') at the
REPL, both of which give an empty string object.
On my machine:
repr('')
'\'\''
Han
Well, I was kinda winging it and didn't actually use the interpreter
for some of those. The point is that the output I gave _could_
reasonably be that of the interpreter (if the implementation details
of repr() were slightly different; it would still meet the spec
anyway) and illustrates the eval()-repr() relationship.
Just keep in mind the equivalence rule and what repr() does should
become obvious.
Cheers,
Chris
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Re: Why no lexical scoping for a method within a class?
On Wed, Dec 17, 2008 at 4:03 PM, Rhodri James rho...@wildebst.demon.co.uk wrote: On Wed, 17 Dec 2008 15:19:32 -, walterbyrd walterb...@iname.com wrote: However in the methods are within a class, the scoping seems to work differently. Not really. Hopefully this commentary will show you why. class ab(): def a(self): self.x = 99 print self.x def b(self): print self.x i = ab() This creates |i|, an instance of class |ab|. As yet it is pure and virgin, having nothing but the methods that it gets from |ab|. Soon this will change... i.a() This creates an attribute |x| in |i|, and assigns the number 99 to it. i.b() # this works, why no lexical scoping? This works because you ran |i.a()| first, so |i.x| exists and can be printed out. Lexical scoping is going on here, you're just mistaking what's being scoped; it's the |self| in |b|, which is in scope because it's a parameter. This particular |self| (the |i| you made earlier) happens to have an attribute |x|, so it all works. If however you'd written: j = ab() j.b() then Python would whinge mightily at you, claiming that it knoweth naught of this |x| attribute of which you speak, and can it go home now for this is a silly place. The |self| in |b| is still in lexical scope, though. Relatedly, Python has no notion of 'declaring' instance variables in a class (instead, you just create them in __init__ or other methods), and class variables (in Java terminology: 'static' variables) do not constitute a scope for variable lookup. Python is still lexically scoped, it's just that only functions and the globals/toplevel/module-level constitute scopes, not class bodies. Cheers, Chris -- Follow the path of the Iguana... http://rebertia.com -- http://mail.python.org/mailman/listinfo/python-list
[ANN] EuroPython 2009 – Call for Partic ipation!
On behalf of the EuroPython 2009 organisation it is my privilege and honour to announce the 'Call for Participation' for EuroPython 2009! EuroPython is the conference for the communities around Python, including the Django, Zope and Plone communities. This years conference will be held in Birmingham, UK from Monday 29th June to Saturday 4th July 2009. Talk Themes Do you have something you wish to present at EuroPython? Go to http://www.europython.eu/talks/cfp/ for this years themes and submissions criteria, the deadline is on 5th April 2009. Other Talks, Activities and Events Have you got something which does not fit the above? Visit http://www.europython.eu/talks/ . Help Us Out We could use a hand any contribution is welcome, please take a look at http://www.europython.eu/contact/ . Sponsors An unique opportunity to affiliate with the prestigious EuroPython conference! http://www.europython.eu/sponsors/ Spread the Word Improve our publicity by distributing this announcement in your corner of the community, please coordinate this with the organizers: http://www.europython.eu/contact/ General Information For more information about the conference, please visit http://www.europython.eu/ Looking forward to see you! The EuroPython Team -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
On Dec 17, 1:21 pm, Jean-Paul Calderone exar...@divmod.com wrote:
On Wed, 17 Dec 2008 11:52:17 -0800 (PST), Rominsky john.romin...@gmail.com
wrote:
On Dec 17, 10:59 am, Christian Heimes li...@cheimes.de wrote:
Rominsky schrieb:
I am trying to use dir to generate a list of methods, variables, etc.
I would like to be able to go through the list and seperate the
objects by type using the type() command, but the dir command returns
a list of strings. When I ask for the type of an element, the answer
is always string. How do I point at the variables themselves. A
quick example is:
a = 5
b = 2.0
c = 'c'
lst = dir()
for el in lst:
print type(el)
for name, obj in vars().iteritems():
print name, obj
Christian
I do have some understanding of the pythonic methodology of
programming, though by far I still don't consider myself an expert.
The problem at hand is that I am coming from a matlab world and trying
to drag my coworkers with me. I have gotten a lot of them excited
about using python for this work, but the biggest gripe everytime is
they want their matlab ide. I am trying to experiment with making
similar pieces of the ide, in particular I am working on the workspace
window which lists all the current variables in the namespace, along
with their type, size, value, etc I am trying to create a python
equivalent. I can get dir to list all the variables names in a list
of strings, but I am trying to get more info them. hence the desire
to do a type command on them. I like the locals and globals commands,
but I am still trying to get more info. I have started using the eval
command with the strings, which is working, but I am curious if there
is a better or more elegant way of getting the info. The eval example
would be something like:
a = 5
b = 2.0
c = 'c'
lst = dir()
for el in lst:
print el + '\t' + str(eval('type(%s)'%el))
It works, now I am curious if there is a better way.
What about this:
for name, obj in vars().iteritems():
print name, obj
Christian
Jean-Paul
vars seems to give an identical response as locals and globals, at
least in my test name space. All three are new commands for me. I
like the idea of adopting either vars or locals instead of dir as it
sets up the value for me to use. I will play with them both a little
more and read up on them to learn there uses and limitations. The key
step for me is still to be able to automatically query the key names
from vars or locals for what type the variable is. In my previous
post I discussed using eval and the string in the key name such as
eval('type(%s)'%vars().keys()[0])
I definitely have enough to move forward. Thanks everyone. If anyone
has any other ideas I would still be interested in learning more.
Thanks again.
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Re: C API and memory allocation
En Wed, 17 Dec 2008 21:35:04 -0200, Floris Bruynooghe floris.bruynoo...@gmail.com escribió: On Dec 17, 11:06 pm, Floris Bruynooghe floris.bruynoo...@gmail.com wrote: So I'm assuming PyArg_ParseTuple() must allocate new memory for the returned string. However there is nothing in the API that provides for freeing that allocated memory again. I've dug a little deeper into this and found that PyArg_ParseTuple (and friends) end up using PyString_AS_STRING() (Python/getargs.c:793) which according to the documentation returns a pointer to the internal buffer of the string and not a copy and that because of this you should not attempt to free this buffer. Yes; but you don't have to dig into the implementation; from http://docs.python.org/c-api/arg.html : s (string or Unicode object) [const char *] Convert a Python string or Unicode object to a C pointer to a character string. You must not provide storage for the string itself; a pointer to an existing string is stored into the character pointer variable whose address you pass. But how can python now know how long to keep that buffer object in memory for? It doesn't - *you* have to ensure that the original string object isn't destroyed (by example, incrementing its reference count as long as you keep the pointer), or copy the string contents into your own buffer. -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess.Popen inheriting
On Dec 17, 5:05 pm, Gabriel Genellina gagsl-...@yahoo.com.ar wrote: En Wed, 17 Dec 2008 12:21:38 -0200, Jeremy Sanders jeremy+complangpyt...@jeremysanders.net escribió: Aaron Brady wrote: I thought so too. The web seems to say that on Linux they are, and on Windows, you need to call DuplicateHandle for it. Or set bInheritHandle=True when creating the pipe initially. os.pipe() doesn't do that. I hit this problem - it looks like pipes aren't very versatile on Windows. There's also the complicating factor that the handles in windows aren't the same as the file numbers that Python uses, so you have to convert between them. It would be nice if Python created pipes that are properly inheritable by default by child processes, as they're mostly used for IPC. I'd say it is a bug in os.pipe implementation; they should be inheritable by default, as in posix (after all, the code is in posixmodule.c). The code looks like this: ok = CreatePipe(read, write, NULL, 0); Py_END_ALLOW_THREADS if (!ok) return win32_error(CreatePipe, NULL); read_fd = _open_osfhandle((Py_intptr_t)read, 0); write_fd = _open_osfhandle((Py_intptr_t)write, 1); 'If lpPipeAttributes is NULL, the handle cannot be inherited.' You could populate a 'SECURITY_ATTRIBUTES' structure, or call DuplicateHandle on both of them. A patch would look like this: SECURITY_ATTRIBUTES sattribs; sattribs.nLength = sizeof(sattribs); sattribs.lpSecurityDescriptor = NULL; sattribs.bInheritHandle = TRUE; ok = CreatePipe(read, write, sattribs, 0); This still doesn't answer whether the file descriptor return by '_open_osfhandle' can be inherited too. -- http://mail.python.org/mailman/listinfo/python-list
Re: C API and memory allocation
On Dec 17, 6:42 pm, Gabriel Genellina gagsl-...@yahoo.com.ar wrote: En Wed, 17 Dec 2008 21:35:04 -0200, Floris Bruynooghe floris.bruynoo...@gmail.com escribió: Yes; but you don't have to dig into the implementation; from http://docs.python.org/c-api/arg.html: s (string or Unicode object) [const char *] Convert a Python string or Unicode object to a C pointer to a character string. You must not provide storage for the string itself; a pointer to an existing string is stored into the character pointer variable whose address you pass. But how can python now know how long to keep that buffer object in memory for? It doesn't - *you* have to ensure that the original string object isn't destroyed (by example, incrementing its reference count as long as you keep the pointer), or copy the string contents into your own buffer. I missed something. How did you get a reference to the original string object, with which to increment its reference count? How do you know its length to copy it into your own buffer? -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Wed, 17 Dec 2008 22:19:43 +0100, Bruno Desthuilliers wrote: Your problem is that you are confusing variables and attributes. In Python, 'anything.anyname' (note the dot) is the attribute 'anyname' of object 'anything'. An easy mistake to make, given that scopes are just namespaces, and attribute access is just accessing names in namespaces too. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess.Popen inheriting
En Wed, 17 Dec 2008 22:46:32 -0200, Aaron Brady castiro...@gmail.com escribió: On Dec 17, 5:05 pm, Gabriel Genellina gagsl-...@yahoo.com.ar wrote: En Wed, 17 Dec 2008 12:21:38 -0200, Jeremy Sanders jeremy+complangpyt...@jeremysanders.net escribió: It would be nice if Python created pipes that are properly inheritable by default by child processes, as they're mostly used for IPC. I'd say it is a bug in os.pipe implementation; they should be inheritable by default, as in posix (after all, the code is in posixmodule.c). The code looks like this: ok = CreatePipe(read, write, NULL, 0); Py_END_ALLOW_THREADS if (!ok) return win32_error(CreatePipe, NULL); read_fd = _open_osfhandle((Py_intptr_t)read, 0); write_fd = _open_osfhandle((Py_intptr_t)write, 1); 'If lpPipeAttributes is NULL, the handle cannot be inherited.' You could populate a 'SECURITY_ATTRIBUTES' structure, or call DuplicateHandle on both of them. A patch would look like this: SECURITY_ATTRIBUTES sattribs; sattribs.nLength = sizeof(sattribs); sattribs.lpSecurityDescriptor = NULL; sattribs.bInheritHandle = TRUE; ok = CreatePipe(read, write, sattribs, 0); Yes, that's exactly how os.popen does it (in posixmodule.c) This still doesn't answer whether the file descriptor return by '_open_osfhandle' can be inherited too. It doesn't matter. The OS only cares about file handles, not C RTL structures. -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: Why no lexical scoping for a method within a class?
On Wed, 17 Dec 2008 10:20:21 -0800, walterbyrd wrote: On Dec 17, 10:00 am, r rt8...@gmail.com wrote: When writing procedural code how would you like it if vars inside functions were automatically global. Your code with be blowing chunks in no time. That was my point - I consider python's ordinary use of lexical scoping to be a good thing, and I was wondering why this good thing was not used in classes, as well as outside of classes. But it is. You're mistaking lexical scoping for object attribute access. The rules for lexical scoping inside a class are (almost) the same as they are for inside a function: def parrot(breed): def message(colour): return The %s %s has beautiful plumage. % (breed, colour) return message(Blue) class Parrot: def parrot(self, breed): def message(colour): return The %s %s has beautiful plumage. % (breed, colour) return message(Blue) And in use: parrot(Norwegian) 'The Norwegian Blue has beautiful plumage.' p = Parrot() p.parrot(Swedish) 'The Swedish Blue has beautiful plumage.' Notice that to have lexical scoping work, you actually have to nest the functions. Otherwise they are in different scopes. This might lead you believe you can do this: class Parrot2: colour = Blue def parrot(self, breed): return The %s %s has beautiful plumage. % (breed, colour) p = Parrot2() p.parrot(Norwegian) Traceback (most recent call last): File stdin, line 1, in module File stdin, line 4, in parrot NameError: global name 'colour' is not defined What's going on? Why doesn't the parrot method see the name colour in the class scope? The reason is that the class scope is deliberately left out of the nested scope chain. This was a design decision from when nested scopes were introduced: An alternative would have been to allow name binding in class scope to behave exactly like name binding in function scope. This rule would allow class attributes to be referenced either via attribute reference or simple name. This option was ruled out because it would have been inconsistent with all other forms of class and instance attribute access, which always use attribute references. Code that used simple names would have been obscure. http://www.python.org/dev/peps/pep-0227/ So inside the method, you need to refer to Parrot.colour (or thanks to the rules of attribute inheritance, self.colour). Classes could be closures, but that could radically change the way methods and classes work. Depending on design decisions, it might require huge changes to the Python compiler. How would it change the existing lexical scoping in factory functions? def factory(colour): class Parrot: def parrot(self, breed): return The %s %s has beautiful plumage. % (breed, colour) return Parrot redparrot = factory(Red)() redparrot.parrot(Swedish) 'The Swedish Red has beautiful plumage.' Consider a hypothetical Python with classes included in the lexical scoping: class Parrot3: colour = Blue def parrot(self): colour = Red What should method parrot do? I can think of at least three possibilities: * create a local name colour inside the method scope; * change the class attribute Parrot3.colour to Red; * create an instance attribute self.colour. Whatever solution you come up with, there is potential inconsistency with other parts of the language. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: C API and memory allocation
En Wed, 17 Dec 2008 22:51:03 -0200, Aaron Brady castiro...@gmail.com escribió: On Dec 17, 6:42 pm, Gabriel Genellina gagsl-...@yahoo.com.ar wrote: En Wed, 17 Dec 2008 21:35:04 -0200, Floris Bruynooghe floris.bruynoo...@gmail.com escribió: But how can python now know how long to keep that buffer object in memory for? It doesn't - *you* have to ensure that the original string object isn't destroyed (by example, incrementing its reference count as long as you keep the pointer), or copy the string contents into your own buffer. I missed something. How did you get a reference to the original string object, with which to increment its reference count? From the original arguments to the function -- the first argument you pass to PyArg_ParseTuple co. How do you know its length to copy it into your own buffer? Use the s# format instead, which returns both a pointer to the string contents and its length. Even if you're not going to copy the buffer, it's required in case the string could contain any NUL byte. -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list
Re: The rule of literal string
On Wed, 17 Dec 2008 15:25:41 -0800, Chris Rebert wrote:
2008/12/17 Li Han lihang9...@gmail.com:
On 12月18日, 上午7时12分, Scott David Daniels scott.dani...@acm.org
wrote:
Scott wrote:
Try: print repr(repr('))
that might enlighten you.
I found that print( repr( repr( arbitarystring ) ) ) == repr (
arbitarystring )
As I stated previously, the key rule is:
eval(repr(something)) == something
That is, repr() gives a string of Python code that, when evaluated,
results in what you gave to repr().
That is not true in general.
from urllib2 import HTTPError
h = HTTPError(404 quoth the Raven, None, None, None, None)
eval(repr(h))
Traceback (most recent call last):
File stdin, line 1, in module
File string, line 1, in module
TypeError: __init__() takes exactly 6 arguments (1 given)
Even for built-ins, it's not always true:
eval(repr(float('inf')))
Traceback (most recent call last):
File stdin, line 1, in module
File string, line 1, in module
NameError: name 'inf' is not defined
In other words, there is no guarantee that repr(obj) will round-trip
correctly, or at all. It's a Nice To Have, and it will often work, but
it's not something you should rely on for arbitrary objects.
However, I believe it is true for strings.
--
Steven
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Re: The rule of literal string
On Thu, 18 Dec 2008 09:34:12 +1000, James Mills wrote: On Thu, Dec 18, 2008 at 9:25 AM, Chris Rebert c...@rebertia.com wrote: As I stated previously, the key rule is: eval(repr(something)) == something This rule is only true for basic data types; Oops, missed this, and the follow ups. Note to self: read thread *before* replying. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: getting object instead of string from dir()
On Wed, 17 Dec 2008 11:52:17 -0800, Rominsky wrote: I do have some understanding of the pythonic methodology of programming, though by far I still don't consider myself an expert. The problem at hand is that I am coming from a matlab world and trying to drag my coworkers with me. I have gotten a lot of them excited about using python for this work, but the biggest gripe everytime is they want their matlab ide. I am trying to experiment with making similar pieces of the ide, in particular I am working on the workspace window which lists all the current variables in the namespace, along with their type, size, value, etc I am trying to create a python equivalent. Have you considered looking at existing IDEs instead of re-inventing the wheel? Python even comes with one, IDLE. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
