Param decorator - can you suggest improvements
I thought it would be interesting to try to implement Scheme SRFI 39 (Parameter objects) in Python. The idea is that you define a function that returns a default value. If you call that function with no arguments, it returns the current default. If you call it with an argument, it resets the default to the value passed in. Here's a working implementation: # http://www.artima.com/weblogs/viewpost.jsp?thread=240845 from functools import wraps class Param(object): def __init__(self, default): self.default = default #self.func = func def __call__(self, func, *args): @wraps(func) def wrapper(*args): #print 'calling hi' if len(args) >0: self.default = args[0] #print len(args), ' ', args return self.default # self.func(*args) return wrapper @Param(42) def hi(newval): pass print hi() # 42 print hi(12) # 12 print hi() # 12 hi(13) # sets it to 13 print hi() # 13 Can anyone suggest a better implementation? -- http://mail.python.org/mailman/listinfo/python-list
Re: Google spreadsheets - getting started
OK, the story so far:
import gdata
import gdata.auth
import gdata.gauth
import gdata.docs.service
import OpenSSL.crypto
tokenfile = "privatekey.p12"
#f = open(tokenfile, 'r')
#blob = f.read()
#f.close()
#if blob:
p12 = OpenSSL.crypto.load_pkcs12(file(tokenfile, 'rb').read(), 'notasecret')
print p12.get_certificate()
#token = gdata.gauth.token_from_blob(p12)
#print "token: ", token
gd_client = gdata.docs.service.DocsService()
#gd_client.SetOAuthToken(token)
gd_client.SetOAuthToken(p12)
feed = gd_client.GetDocumentListFeed() # line 22
for entry in feed.entry:
print entry.title.text.encode('UTF-8')
print "Finished"
It baulks as follows:
/usr/bin/python -u "/home/mcarter/wapp.py"
Traceback (most recent call last):
File "/home/mcarter/wapp.py", line 22, in
feed = gd_client.GetDocumentListFeed()
File "/usr/lib/pymodules/python2.7/gdata/docs/service.py", line 259, in
GetDocumentListFeed
return self.QueryDocumentListFeed(uri)
File "/usr/lib/pymodules/python2.7/gdata/docs/service.py", line 238, in
QueryDocumentListFeed
return self.Get(uri, converter=gdata.docs.DocumentListFeedFromString)
File "/usr/lib/pymodules/python2.7/gdata/service.py", line 1068, in Get
headers=extra_headers)
File "/usr/lib/pymodules/python2.7/atom/__init__.py", line 92, in
optional_warn_function
return f(*args, **kwargs)
File "/usr/lib/pymodules/python2.7/atom/service.py", line 184, in request
return auth_token.perform_request(self.http_client, operation, url,
AttributeError: 'PKCS12' object has no attribute 'perform_request'
What??
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Re: Google spreadsheets - getting started
OK, maybe the p12 file is useful after all (?) I've got the following code: import gdata tokenfile = "my-privatekey.p12" f = open(tokenfile, 'r') blob = f.read() f.close() token = gdata.gauth.token_from_blob(blob) When I run that I get: Traceback (most recent call last): File "/home/mcarter/wapp.py", line 8, in token = gdata.gauth.token_from_blob(blob) AttributeError: 'module' object has no attribute 'gauth' I guess I'm using a newer version of gdata (2.0.14). None of this makes any sense. -- http://mail.python.org/mailman/listinfo/python-list
Google spreadsheets - getting started
I want to mess around with my online Google spreadsheets from my Linux box programmatically. I am TOTALLY confused. I've got gdata installed, and it appears that the best way to access the spreadsheets is to authenticate with Oauth2. Here's the main thing: how do I get an Oauth2 key to use with Google spreadsheets? I obtain a "p12" key, but I don't know if that's for something completely different. -- http://mail.python.org/mailman/listinfo/python-list
Re: Guarding arithmetic
On Thursday, 23 August 2012 10:23:20 UTC+1, Laszlo Nagy wrote: > On 2012-08-23 11:05, Mark Carter wrote: > You are very vague. "There is an error" - but what kind of error? Assume that it doesn't matter. > In some special cases, this can be a good idea to do. Those are the cases that I'm interested in. -- http://mail.python.org/mailman/listinfo/python-list
Re: Guarding arithmetic
On Thursday, 23 August 2012 10:16:08 UTC+1, Chris Angelico wrote: > On Thu, Aug 23, 2012 at 7:05 PM, Mark Carter <> wrote: > > Suppose I want to define a function "safe", which returns the argument > > passed if there is no error, and 42 if there is one. > only possible with floating point, not integer. > > try: > print 1/0 > except ZeroDivisionError: > print 42 OK, so it looks like a solution doesn't exist to the problem as specified. I guess it's something that only a language with macros could accommodate. -- http://mail.python.org/mailman/listinfo/python-list
Guarding arithmetic
Suppose I want to define a function "safe", which returns the argument passed if there is no error, and 42 if there is one. So the setup is something like: def safe(x): # WHAT WOULD DEFINE HERE? print safe(666) # prints 666 print safe(1/0) # prints 42 I don't see how such a function could be defined. Is it possible? -- http://mail.python.org/mailman/listinfo/python-list
Re: Looking for a urllib(2) cookie handler
On Apr 19, 12:44 pm, Mark Carter wrote:
> url and say "just use the cookie that I have in Firefox"?
"mechanize" looks kinda like what I want, but i still can't get it to
work properly. So far I have:
import cookielib
import mechanize
cookiefile = "C:\\Users\\$ME\\AppData\\Roaming\\Mozilla\\Firefox\
\Profiles\\zl648qvt.default\\cookies.sqlite"
cookies = mechanize.MozillaCookieJar(filename = cookiefile,
delayload=True)
#cookies = cookielib.MozillaCookieJar()
#cookies = cookielib.MSIECookieJar()
#cookies.load_from_registry() # finds cookie index file from registry
br = mechanize.Browser()
br.set_cookiejar(cookies)
br.addheaders = [('User-agent', 'Mozilla/5.0 (X11; U; Linux i686; en-
US; rv:1.9.0.1) Gecko/2008071615 Fedora/3.0.1-1.fc9 Firefox/3.0.1')]
url = "$URL"
r = br.open(url)
#print cj
#opener =
mechanize.build_opener(mechanize.HTTPCookieProcessor(cookies))
html = r.read()
print html
where $ME and $URL are replaced with suitable values. It doesn't
appear to acutally be "using" the cookies.
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Looking for a urllib(2) cookie handler
I'm in python 2.6.5, and have Firefox 3.6.13. I would like to download some html from a site and scrape it programatically. The site requires a cookie, which I have in Firefox. Is there a simple python recipe I can use to read the contents of a url and say "just use the cookie that I have in Firefox"? -- http://mail.python.org/mailman/listinfo/python-list
Re: wx.Frame hidden, and customising the close button
On Feb 11, 1:39 pm, Vlastimil Brom wrote: > (wxPython-specific questions may be rather discussed on that > maillist:http://groups.google.com/group/wxpython-users/topics?pli=1 Just the ticket! Many thanks! -- http://mail.python.org/mailman/listinfo/python-list
wx.Frame hidden, and customising the close button
Is there a way of testing whether a frame (suppose I have it as a variable my_frame) is hidden in wxPython? Also, is there a way that I can over-ride the close button so that the frame becomes hidden rather than destroyed, and perform supplementary tests? -- http://mail.python.org/mailman/listinfo/python-list
Printing RTF file under win32
I'm using Python 2.6.5 on win32. I would like to print a batch of RTF files on a printer. I don't want to use the win32api.ShellExecute command because that invokes Word, and Word has been configured in a strange way by one of our admins, making it inconvenient to use. What should I do? -- http://mail.python.org/mailman/listinfo/python-list
wx Just Print!
I'm using Python 2.6.5. I would like to be able to print an RTF file,
with no prompts for printers or anything like that.
Here's the code so far:
import wx.richtext
rtp = wx.richtext.RichTextPrinting()
rtp.PrintFile('C:\\path\\to\\file.rtf')
When I run it, it says: ... assert "(wxThePrintPaperDatabase*) NULL)
failed ...
What is the fix?
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Python scripts from DOS
On my machine, I can go to a DOS shell, and type myscript.py This will cause the script to be run as a python script. So that bit works. On another machine, on which python was set up without admin privileges, if I type myscript.py it will open the "Open With" dialog box. It wont let me execute it with python.exe. It asks me the same question every time, too. If I type python myscript.py then everything works fine. Is there a way of setting up the "other" machine so that it replicates the behaviour of my machine? -- http://mail.python.org/mailman/listinfo/python-list
win32com sql update problem
Consider the following snippet of code:
import win32com.client
DSN = 'PROVIDER=Microsoft.Jet.OLEDB.4.0;DATA SOURCE=M:\\Finance\\camel\
\camel.mdb;'
conn.Open(DSN)
cursor = conn.Execute("UPDATE tblInvoice SET InvComments='Python'
WHERE InvBillingPeriod = 'April 2010' AND InvJobCode = '2169'")
rows = cursor.Affected_Rows()
print rows
conn.Close()
I am using Python 2.6.5, and pywin32. If I try to run it, I get the
response:
Traceback (most recent call last):
File "C:/Users/mcarter/tacc/pypms/post.py", line 79, in
AdjustPms(d)
File "C:/Users/mcarter/tacc/pypms/post.py", line 64, in AdjustPms
cursor = conn.Execute("UPDATE tblInvoice SET InvComments='Python'
WHERE InvBillingPeriod = 'April 2010' AND InvJobCode = '2169'")
File "", line 3, in Execute
File "C:\Python26\lib\site-packages\win32com\client\dynamic.py",
line 272, in _ApplyTypes_
result = self._oleobj_.InvokeTypes(*(dispid, LCID, wFlags,
retType, argTypes) + args)
pywintypes.com_error: (-2147352567, 'Exception occurred.', (0,
u'Microsoft JET Database Engine', u"Cannot open database ''. It may
not be a database that your application recognizes, or the file may be
corrupt.", None, 5003049, -2147467259), None)
I have used the same DNS to retrieve data from the database using
SELECT statements, so I'm at a loss to figure out what's going wrong.
It seems to think the database name as an empty string. I'm not sure
if that's the root cause of the problem, though. Any ideas?
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Re: Install 2.6.4 as non-admin on Windows
On 18 Mar, 15:23, "egl...@gmail.com" wrote: > The only file written to a system folder is python2x.dll (I think it's > not true for python2.6 any longer), so your approach is perfectly > valid if you can put this dll into a folder where it can be found by > the system. Thanks. That sounds easy enough to do. I guess it's the same deal with win32all. -- http://mail.python.org/mailman/listinfo/python-list
Install 2.6.4 as non-admin on Windows
How do I install python 2.6.4 on Windows without admin privileges? Can I install it on a machine I control, zip up the contents, copy it across to an admin-restricted machine, and set up a couple of environemtn variables? Does python install files to system directories, making this impossible? -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting started with OS X Leopard
[EMAIL PROTECTED] wrote: > if you are not satisfied with the native version, why not install the > official version directly from python site > http://www.python.org/download/ (macpython) instead of using that of > macports. It moreover is provided with many utilities > > There is a macpython list that you can consult at > http://www.nabble.com/Python---pythonmac-sig-f2970.html Thanks. Actually, I created my first python appscript (well, "stole" it from a previous poster is more like it) - and it's pretty cool when I combine it with FinderPop. -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting started with OS X Leopard
Arnaud Delobelle wrote: > Is there a particular reason you want python from MacPorts? OSX > Leopard comes with python 2.5, that's what I use on my mac. I heard from somewhere that Apple's version was a bit wonky, and that I would be better off with a "proper" build. -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting started with OS X Leopard
has wrote: > On 15 Mar, 18:05, Mark Carter <[EMAIL PROTECTED]> wrote: >> The sorts of things I want to do are: >> * copy the directory of Finder to the clipboard >> * add a new file to Finder's directory. >> * find out the size of a directory >> * open a file with Aquamacs, regardless of file type, > > If you want to control desktop applications directly, that generally > means using Apple event IPC. The most popular language for application > scripting is traditionally AppleScript, but Apple event bridges exist > for other languages as well. The best of these is appscript; see my > sig for links. Some Finder scripting examples: > > > #!/usr/bin/python > ... > Control AppleScriptable applications from Python, Ruby and ObjC: > http://appscript.sourceforge.net Aah! Many thanks. I see that I had to do easy_install appscript and ensure I use /usr/bin/python I'm off to play with it now. Exciting stuff. I installed the Python from MacPorts. That's not quite what I wanted, because they only have a version for Python 2.4. *Sigh*. MacPorts seems to be getting new ports all the time. The problem is, there also seems to be an aweful lot of ports gathering bitrot. Am I the only one to form the opinion that OS X can sometimes appear to be a bit of a mish-mash? I tried XCode the other day. Seemed a bit complicated, if you ask me. I've tried to like Lisp, too. In the end, Python just rocks. I started out with Glade a short while ago, and I'm impressed how relatively easy it is to create GUIs and add handlers in Python. -- http://mail.python.org/mailman/listinfo/python-list
Getting started with OS X Leopard
One thing I really liked about Ubuntu was that Nautilus allowed you to add scripts to a directory which could be accessed via the RMB. It was a very simple thing to do. I've recently switched to Leopard, and I'm trying to do the same thing. I'm fairly experienced with Python, but new to OS X. I have installed FinderPop, which lets me add scripts and make them accessible via Contextual Menus, but it is not as easy as the Nautilus way. The sorts of things I want to do are: * copy the directory of Finder to the clipboard * add a new file to Finder's directory. * find out the size of a directory * open a file with Aquamacs, regardless of file type, My head's swimming, though. Anyone got any really good pointers and sample scripts that will help me work out how to achieve the sorts of things I'm trying to do? -- http://mail.python.org/mailman/listinfo/python-list
Re: sqlite3 bug??
Carsten Haese wrote: > On Sun, 2007-06-17 at 07:43 -0700, 7stud wrote: >> Please report the whole docs as a bug. > > I imagine the author appreciates constructive criticism. This is not > constructive criticism. > > In other words: Pointing out specific shortcomings and ways to correct > them, such as what the OP is doing, is helpful. Calling the entire docs > a bug is not helpful. You'll be pleased to know that I was specific, and I suggested a change that I thought would be good. Actually, I think the docs are quite good! I went hunting around some Scheme implementations lately. What was immediately apparent to me was that the docs weren't nearly as good as those for python. Typical problems centre about what modules I was supposed to load, and how I was supposed to use them. What might be obvious to an old hand might not be obvious to someone coming in from fresh. This is where big projects like Python tend to score - the docs have been through many iterations. -- http://mail.python.org/mailman/listinfo/python-list
Re: sqlite3 bug??
7stud wrote: > On Jun 17, 7:16 am, mark carter <[EMAIL PROTECTED]> wrote: >> David Wahler wrote: >>> On 6/17/07, mark carter <[EMAIL PROTECTED]> wrote: >>>> Anyone else getting these problems? >>> Seehttp://www.python.org/dev/peps/pep-0249/(emphasis mine): >>>.commit() >> >> I'm seriously thinking about reporting the commit() thing as a doc bug >> in python, as this isn't mentioned at >> http://docs.python.org/lib/module-sqlite3.html >> and I think it's exactly the kind of thing that should be mentioned in >> the examples. > > Please report the whole docs as a bug. http://sourceforge.net/tracker/index.php?func=detail&aid=1738670&group_id=5470&atid=105470 That will save a few people tearing their hair out! -- http://mail.python.org/mailman/listinfo/python-list
Re: sqlite3 bug??
David Wahler wrote: > On 6/17/07, mark carter <[EMAIL PROTECTED]> wrote: >> Anyone else getting these problems? > > See http://www.python.org/dev/peps/pep-0249/ (emphasis mine): > >.commit() OK, I tried that, and I appear to be cooking. The funny thing is, I could have sworn that I tried that a few days ago, and it didn't work. Weird. Appears to be working now, though, so I guess I must have been doing something kooky. Should I also explicitly close the cursor and connection, or is that taken care of "automagically"? I'm seriously thinking about reporting the commit() thing as a doc bug in python, as this isn't mentioned at http://docs.python.org/lib/module-sqlite3.html and I think it's exactly the kind of thing that should be mentioned in the examples. -- http://mail.python.org/mailman/listinfo/python-list
sqlite3 bug??
I hesitate to ask, but ...
I'm using Ubuntu Feisty:
* Python 2.5.1 (r251:54863, May 2 2007, 16:56:35)
[GCC 4.1.2 (Ubuntu 4.1.2-0ubuntu4)] on linux2
* SQLite version 3.3.13
Suppose I run the following program:
import sqlite3
conn = sqlite3.connect('example')
c = conn.cursor()
# Create table
c.execute('''create table stocks
(date text, trans text, symbol text,
qty real, price real)''')
# Insert a row of data
c.execute("""insert into stocks
values ('2006-01-05','BUY','RHAT',100,35.14)""")
and then I go into sqlite:
% sqlite3 example
sqlite3> select * from stocks ;
It returns 0 rows. I'm in the right directory. I have experienced this
problem with some other sqlite3 database work I have done with python,
so I'm figuring there is something fishy going on. I've tried doing
similar exercises with Ruby, and they have worked OK.
Anyone else getting these problems?
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Re: Working with fixed format text db's
Neil Cerutti wrote: > The underlying problem, of course, is the archaic flat-file > format with fixed-width data fields. Even the Department of > Education has moved on to XML for most of it's data files, :( I'm writing a small app, and was wondering the best way to store data. Currently the fields are separated by spaces. I was toying with the idea of using sqlite, yaml or json, but I think I've settled on CSV. Dull, but it's easy to parse for humans and computers. -- http://mail.python.org/mailman/listinfo/python-list
Re: Who uses Python?
Thomas Jollans wrote: > Broadly speaking, everyone who uses python programs in it and may thus be > considered a "programmer". A woman from a job agency 'phoned me up the other day, and asked me if I was any good with "algortihms". I told her that all programs are algorithms, so the question didn't make that much sense. Needless to say, I wasn't offered an interview ;) -- http://mail.python.org/mailman/listinfo/python-list
Re: Who uses Python?
walterbyrd wrote: > Anything else? Finance? Web-analytics? SEO? Digital art? I played with NodeBox a little while ago: http://nodebox.net/code/index.php/Home "NodeBox is a Mac OS X application that lets you create 2D visuals (static, animated or interactive) using Python programming code and export them as a PDF or a QuickTime movie. NodeBox is free and well-documented." Pretty trippy stuff. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python rocks
Alex Martelli wrote: > Josiah Carlson <[EMAIL PROTECTED]> wrote: > >>> pitfall of Python is knowing whether an operation is destructive or not. >> If it returns None, it probably changes the content of an object. > > A reasonable heuristic, but with lots of exceptions, alas: > somedict.get(somekey) > will often return None without performing any change, while > somelist.pop() > does modify somelist but typically returns non-None. > > The use of trailing-exclamation-point (by convention) to indicate > "mutating methods" is a nice plus in languages that allow it. Actually, that'd be nice to have in Python. And whilst we're about it, might as well go the whole hog and allow hyphens in names, too. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python rocks
Alex Martelli wrote: > Mark Carter <[EMAIL PROTECTED]> wrote: > Yes, GMP is a pain to compile (especially on Mac OS X), but I believe > Just mentioning this in case you want to give Scheme another chance Thanks. I'll take a look at it. I think I've decided to finish off my little in project in Python first, though. I'd like to actually get it done (!). I may well decide to reimplement bits in either Scheme, or I might try my hand at Forth. My app will be small enough to permit re-writes. I had actually done a small 3-month Java project professionally about 7 years ago. Can't say I was too impressed. IMO, it was too verbose, I'm not an OO fanatic, and some immutable strings turned out to be not quite as immutable as I expected. I had a brief toy around with Java using Xcode very recently, and I was able to figure out how to download webpages easy enough (I do this to scrape stock quotes). I felt fairly confident that I could achieve what I wanted in Java, even though I'm fairly raw with it. I started from a default project using Xcode, and it seemed to generate a lot of base code. I quickly abandoned the Java idea, as I'm not gunning to be a Java developer, and Python seems to do what I want without fuss. I think that's the key to Python. You can do what you want without fuss, and it's copiously documented. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python rocks
Josiah Carlson wrote:
> Mark Carter wrote:
>> Not that I'm particularly knowledgeable about language design issues,
>> but maybe closures and slightly different scoping rules would be nice.
>
> Python has had closures for years.
I just looked up
http://www.secnetix.de/~olli/Python/lambda_functions.hawk
and was amazed to discover that you were right. Nice one.
> What kind of scoping did you desire?
Well, I had in mind so that if you defined a function, but wanted to
access a global var, that you didn't have to use the global keyword. Not
much of a biggie, I guess.
> Refuse the temptation to guess. As many people want to keep the
> newlines as not (it disambiguates the case of end of file and blank
> line), and it is a simple thing to deal with: line.rstrip('\r\n') .
I guess that about wraps it up, then. Python pretty much has it all.
Except for macros - which is not necessarily a dealbreaker, anyway.
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Re: Python rocks
Steve Howell wrote: > --- Mark Carter <[EMAIL PROTECTED]> wrote: > >> Well, I know I'm preaching to the converted - but >> Python rocks. >> [...] > > A few questions from the choir: > > As a recent newcomer to the language, did you > encounter any traps or pitfalls while you were > learning? Also, could you single out anything in > particular about Python that started making you more > productive, or was it just the overall design? Well, I've been around the block a few times with Python, and had decided to try a couple of other languages. Having poked around, I've come to the conclusion that Python is the best language out there, and thought I'd share my observation with everyone. I hadn't posted to Lisp, because that'd be, like, considered trollish. Python's biggest win is probably its "batteries included" philosophy. Plus its extensive documentation. IDLE is simple, but it gets the job done. The syntax is obvious enough, so there's not much to dislike about Python. Not that I'm particularly knowledgeable about language design issues, but maybe closures and slightly different scoping rules would be nice. A pitfall of Python is knowing whether an operation is destructive or not. I guess if it was a purely functional language, that particular question wouldn't arise. Not that I'm saying I want Python to be a purely functional language. Oh, and when I read a line, I'd like it to get rid of the trailing line-ending characters. Python is accreting a lot of language features, and I'm not sure that's a good idea. Still, I guess if I don't like them, I don't have to use them. The thing about Lisp I found is that it's horribly fragmented, and doesn't do what I want it to do out of the box. Lisp is just too tedious. Python Just Works. I checked out Ruby a couple of years ago, but couldn't find anything to be worth the switch. I'm amazed at some of the things people have been able to do in Forth; but then, it doesn't beat Python's truckload of libraries and stuff like dictionaries, lists and other goodies that I get out of the box. -- http://mail.python.org/mailman/listinfo/python-list
Python rocks
Well, I know I'm preaching to the converted - but Python rocks. I've been enchanted by the siren calls of Scheme, Lisp and Forth, but in the end, I find Python much easier. I even tried a little bit of Tcl. To give a bit of context ... I have recently switched from Windows to OS X and Linux. I missed MS Money, but couldn't get on with GnuCash. So I decided to write my own little home-brew money management program that includes things like downloading share price info from Yahoo Finance. I picked Chicken Scheme for OS X. Things started well, and even the web download and regex stuff worked fairly painlessly. I wanted to work with dates, and decided that I needed the SRFI-19 library. Chicken has "eggs", which you can download and install. The problem is that it needed further dependencies. Well, no need to panic just because of that; but I found that it ultimately depended on gmp, which turned out a pain to compile. Other languages seem to have neat ideas; like closures or macros in Scheme, or ultra-simple syntax like Forth. But what I have generally found is that other languages seem to require too much pain for too little return. I just seem to be way more productive in Python than in any other language. -- http://mail.python.org/mailman/listinfo/python-list
Re: Programming challenge: wildcard exclusion in cartesian products
Mark Carter wrote: > At the risk of being labelled a troll One thing I just discovered, and by which I mean *really* discovered ... is that Lisp is an interactive environment. I am working on trying to verify the contents of disks. I noticed that the input formats are slightly wrong, and needed correction. In fact, there's a whole host of jiggery pokery that I need to do in order to massage and build up everything the way it needs to be. A programmers mindset is usually geared towards "writing applications". What I'm currently doing in Lisp is building up functions as I need them. Using emacs, I can just C-x C-e to make my functions "live", and when it's time to stop for the day, save my working image so that I can use it the next day. It seems to me that only Forth or Scheme really matches this capability. Ruby and Python come kinda close - they do have a REPL, but it's kinda clunky to try to create functions on the fly, plus of course they don't support the idea of an image. -- http://mail.python.org/mailman/listinfo/python-list
Re: Programming challenge: wildcard exclusion in cartesian products
Mark Tarver wrote: > Interesting. At the risk of being labelled a troll, one thought that is occuring to me is that in Lisp it seems that sometimes it is difficult to achieve a simple thing in a simple way. To clarify ... recently, I had been trying to obtain md5 hashes of the files we had on our server (a different exercise than the one I mentioned in my OP, just in case you thought that I didn't understand the difference between encryption and hashing). There is an md5 package for Lisp available on the web, which I used with CLISP. I had a file that contained a non-standard character, causing CLISP to throw an error when it tried to print it. Well, I suppose I could have tried to figure out a way to cajole CLISP into printing something it didn't want to print, but I was keen to give Corman Lisp 2.5 a try-out anyway, so I tried the package on it. EXCEPT, for some reason when you try to read a file with an :element-type of (unsigned-byte 8) (or something similar), Corman didn't like it. In the end, I hacked together an md5 DLL from some sources I found on the internet. You can get the package here, together with Corman Lisp bindings: http://www.markcarter.me.uk/computing/freeware/md5mc/md5mc.htm In the past, I had also employed a similar technique in order to get access to some console functions that I was interested in. My worry is that it seems to be a recurring theme with me ... get stumped in Lisp, realise that it is probably just plain easier in C, and then link the whole thing together in Lisp. Which is kinda less than expected. -- http://mail.python.org/mailman/listinfo/python-list
Re: Programming challenge: wildcard exclusion in cartesian products
I'd like to propose a coding challenge of my own. The challenge is to
reproduce the TEA (Tiny Encryption Algorith):
http://www.simonshepherd.supanet.com/tea.htm
in your language of choice.
Here's the code, just two simple functions:
void encipher(unsigned long *const v,unsigned long *const w,
const unsigned long *const k)
{
register unsigned long y=v[0],z=v[1],sum=0,delta=0x9E3779B9,
a=k[0],b=k[1],c=k[2],d=k[3],n=32;
while(n-->0)
{
sum += delta;
y += (z << 4)+a ^ z+sum ^ (z >> 5)+b;
z += (y << 4)+c ^ y+sum ^ (y >> 5)+d;
}
w[0]=y; w[1]=z;
}
void decipher(unsigned long *const v,unsigned long *const w,
const unsigned long *const k)
{
register unsigned long y=v[0],z=v[1],sum=0xC6EF3720,
delta=0x9E3779B9,a=k[0],b=k[1],
c=k[2],d=k[3],n=32;
/* sum = delta<<5, in general sum = delta * n */
while(n-->0)
{
z -= (y << 4)+c ^ y+sum ^ (y >> 5)+d;
y -= (z << 4)+a ^ z+sum ^ (z >> 5)+b;
sum -= delta;
}
w[0]=y; w[1]=z;
}
I had a crack at it in Lisp. My version doesn't work - but of greater
concern to me is that it doesn't appear nearly as compact as the C
version. Anyway, here's my Lisp code (no prizes for guessing that I'm a
noob to Lisp):
(defconstant delta 2654435769 ) ; delta= 0x9E3779B9
(defun floorn (n) (nth-value 0 (floor n)))
(defun >> (val num-bytes)
"Right-shift positive integer val by num-bytes"
(let* (t1 t2)
(setf t1 (expt 2 num-bytes))
(setf t2 (/ val t1))
(floor t2)))
(defun << (val num-bytes)
"Left-shift positive integer v by num-bytes"
(* val (expt 2 num-bytes)))
(defun <<4 (i) (<< i 4))
(defun byte-n (v n)
"Return the nth byte of a value v"
(let* ((bits-to-shift (* 8 (1- n)))
(shifted-value (>> v bits-to-shift)))
(logand shifted-value 256)))
(defun transform (v1 v2 v3 v4)
(let (t1 t2 t3)
(setf t1 (<<4 v1))
(setf t2 (expt v2 v1))
(setf t3 (expt v3 (>> v2 5)))
(+ t1 t2 t3 v4)))
(defun pack64 (b1 b2) (+ (<< b1 32) b2))
(defun encipher (v k)
(let ((sum 0)
(a (byte-n k 3)) ; a=k[0]
(b (byte-n k 2)) ; b=k[1]
(c (byte-n k 1)) ; c=k[2]
(d (byte-n k 0)) ; d=k[3]
(y (byte-n v 1)) ; y=v[4]
(z (byte-n v 0))) ; z=v[1]
(loop for n from 0 to 31 do ;n=32, while(n-->0)
(incf sum delta);sum += delta;
(incf y (transform z a sum b)) ; y += (z << 4)+a ^ z+sum ^ (z >> 5)+b
(incf z (transform y c sum d)) ;z += (y << 4)+c ^ y+sum ^ (y >> 5)+d;
)
(pack64 y z) ; w[0]=y; w[1]=z;
))
(defun decipher (v k)
(let ((sum 3337565984) ; 0xC6EF3720
(a (byte-n k 3)) ; a=k[0]
(b (byte-n k 2)) ; b=k[1]
(c (byte-n k 1)) ; c=k[2]
(d (byte-n k 0)) ; d=k[3]
(y (byte-n v 1)) ; y=v[4]
(z (byte-n v 0))) ; z=v[1]
(loop for n from 0 to 31 do ;n=32, while(n-->0)
(decf z (transform y c sum d)) ;z -= (y << 4)+c ^ y+sum ^ (y >> 5)+d;
(decf y (transform z a sum b)) ;y -= (z << 4)+a ^ z+sum ^ (z >> 5)+b;
(decf sum delta);sum -= delta;
)
(pack64 y z) ; w[0]=y; w[1]=z;
))
--
http://mail.python.org/mailman/listinfo/python-list
Re: Windows and python execution
rzed wrote: > I should have asked which Windows version you had. XP Pro My bad. On Win2k > or XP, adding .py (for instance) to the PATHEXT variable means that > you can execute "myNeatProgram.py" with this command-line: > prompt>myNeatProgram Oh, now I see! It's beginning to make sense to me. I'll have to try that out. Thanks for the tip. -- http://mail.python.org/mailman/listinfo/python-list
Re: Windows and python execution
Bengt Richter wrote: >>>And there is a PATHEXT environment variable, >> >>Aha. You'bve provided a significant clue. >> >>What you need to do is include the following line in autoexec.bat: >>set .py=c:\python24\python.exe >> >>This will achieve the desired result. I'm suprised more people don't use it. > > I wasn't aware of that syntax for set. What OS/platform/shell is that from? Windows XP, bog-standard default shell. UNIXers have it easy because they can use the normal "shebang". > How did you go from the PATHEXT "clue" to the set command you specify I can't remember. It was a bit of luck, I think. I happened upon: http://www.jpsoft.com/help/index.htm?exeext.htm probably as a result of Googling for PATHEXT. > and decide > not to set pathext, e.g., by something like > set PATHEXT=%PATHEXT%;.py > Does your set do the pathext and assoc and ftype all in one swell foop? Actually, I haven't figured out what PATHEXT is actually supposed to "do". It seemed to me that Windows couldn't possibly know that a py file should be started by python.exe, whereas my set .py= ... would. I had installed python 2.4 in the standard way, so py files were already associated with python when you double-clicked them from Explorer. Using my set meant that if I wanted to use py files from the command line, I could just type out the script name (you have to be in the right directory, of course), and it works. Here's a snippit from my autoexec.bat files: set PATH=C:\python24;%PATH% set .py=c:\python24\python.exe -- http://mail.python.org/mailman/listinfo/python-list
Re: Windows and python execution
BartlebyScrivener wrote: > The installer can put python.exe in his PATH but if he's storing his > scripts in some oddball place then he has to tell Windows where to find > them. I think you're misunderstanding what I was after. python.exe is already in my PATH. What I was trying to do was execute a python script without having to type the word "python" explicitly. For that, you need the "set" command that I listed in a previous post. Anyway, I want to be able to put my scripts in "oddball" places, as they form part of separate projects rather than a generally-runnable script. It doesn't matter to me that Windows cannot find the script itself - because I just go to the directory where's it's at. The upshot is that my original problem has now been solved, and that discussing the matter further will only likely confuse the issue. -- http://mail.python.org/mailman/listinfo/python-list
Re: Windows and python execution
rzed wrote: > Mark Carter <[EMAIL PROTECTED]> wrote in > news:[EMAIL PROTECTED]: > > >>What I would like to do it type something like >> >>>myscript.py >> >>instead of >> >>>python myscript.py > As another poster points out, be sure that your Python is on your > path. > > And there is a PATHEXT environment variable, Aha. You'bve provided a significant clue. What you need to do is include the following line in autoexec.bat: set .py=c:\python24\python.exe This will achieve the desired result. I'm suprised more people don't use it. -- http://mail.python.org/mailman/listinfo/python-list
Windows and python execution
What I would like to do it type something like > myscript.py instead of > python myscript.py on a Windows console. I know its possible because Ruby scripts manage to do this - I just don't know the registry settings that need to be tweaked to enable it. Any ideas (I'd prefer to know the registry settings rather than a graphical way to accomplish the goal)? -- http://mail.python.org/mailman/listinfo/python-list
Passwords in cron scripts
I have some python scripts that run as cron jobs. They connect to external resources (like a newsserver) - for which passwords are required. I currently have them stored in the scripts themselves (ouch!) - and was wondering if there was a more secure solution. -- http://mail.python.org/mailman/listinfo/python-list
Re: Xah's Edu Corner: Responsible Software Licensing
robic0 wrote: > Xah, please admit to me that your under the influence of > physocopic drugs! He could be schizophrenic. Seekers of all things wierd on the internet can do no better than Gene Ray's Timecube: http://www.timecube.com/ His outpourings are so well known that he even gets a mention in the wikipedia: http://en.wikipedia.org/wiki/Gene_Ray And once you've fully absorbed the fact that "You are educated as a stupid android slave to the evil Word Animal Singularity Brotherhood", why not play the game of the theory over at: http://atrocities.primaryerror.net/timecube.html -- http://mail.python.org/mailman/listinfo/python-list
Re: Web functions idea
bruno at modulix wrote: > Mark Carter wrote: > Congratulations, you've just rediscovered REST !-) Huzzah! > Turbogears is probably what you're looking for (if not quite what you > describe). Thanks. It looks quite interesting. -- http://mail.python.org/mailman/listinfo/python-list
Web functions idea
I was musing recently about how one could, for example, set up a really simple mailing subscription list. It occurred to me that a really simple way to implement it would be to use xmlrpc. So there could be a function subscribe(emailAddress), which would send an email for confirmation, and another function confirm(emailAddress, password) which would confirm the address ... and so on. Now, the problem is that, if you use xmlrpc, it requires some kind of fiddly software that the client would have to install. What you would really want is some kind of web interface instead of xmlrpc - a kind of "web driven xmlrpc" (that would eliminate the need of an actual xmlrpc server). The point of it being this: a developer would just write the functions that he needed, a la xmlrpc, which would be "exposed" to this new module (let's call it webrpc) - and webrpc would examine the function, work out how many arguments it had, and display a form for the user to fill out. From an application writer's point-of-view, it abstracts away the whole web process, leaving him free to just concentrate on the underlying function implementation. -- http://mail.python.org/mailman/listinfo/python-list
Re: Port blocking
Ed Leafe wrote: On Jan 10, 2005, at 8:00 PM, Steve Holden wrote: There isn't, IMHO, anything with the polish of (say) Microsoft Access, or even Microsoft SQL Server's less brilliant interfaces. Some things Microsoft *can* do well, it's a shame they didn't just stick to the knitting. Though it's certainly not anywhere near the polish of Access, you should check out Dabo. Thanks. I'll look into it. -- http://mail.python.org/mailman/listinfo/python-list
Re: Port blocking
Mark Carter wrote: Paul Rubin wrote: Usually you wouldn't run a public corba or pyro service over the internet. You'd use something like XMLRPC over HTTP port 80 partly for the precise purpose of not getting blocked by firewalls. I'm not sure if we're talking at cross-purposes here, but the application isn't intended for public consumption, but for fee-paying clients. -- http://mail.python.org/mailman/listinfo/python-list
Re: Port blocking
Paul Rubin wrote: Mark Carter <[EMAIL PROTECTED]> writes: Supposing I decide to write a server-side application using something like corba or pyro. Usually you wouldn't run a public corba or pyro service over the internet. You'd use something like XMLRPC over HTTP port 80 partly for the precise purpose of not getting blocked by firewalls. Although, when you think about it, it kinda defeats the purposes of firewalls. Not that I'm criticising you personally, you understand. Also, is there a good tool for writing database UIs? Yes, quite a few. Ah yes, but is there really? For example, I did a search of the TOC of GTK+ Reference Manual: http://developer.gnome.org/doc/API/2.0/gtk/index.html for the word "data", and there's apparently no widget which is explicitly tied to databases. So in GTKs case, for instance, it looks like one has to roll one's own solution, rather than just using one out of the box. -- http://mail.python.org/mailman/listinfo/python-list
Port blocking
Supposing I decide to write a server-side application using something like corba or pyro. What's the chance that in big corporations, the client's ports (in both senses of the word: fee-paying, and application) will be blocked, thereby immediately scuppering whatever I have written? Has this problem ever arisen for anyone? Also, is there a good tool for writing database UIs? -- http://mail.python.org/mailman/listinfo/python-list
Re: How can engineers not understand source-code control?
Mark Carter wrote: I'm thinking that the I-Ching is a vast untapped resource for programming wisdom, plus it makes it funny. Well, carrying on in the same frivilous and some might say off-topic mood, I did a bit of a Google, and found that you can generate your very own I-Ching reading: http://www.grillet.co.uk/iching/ According to the link at: http://www.grillet.co.uk/iching/casting.html "The I Ching is a good guide in taking decisions when you have no rational basis on which to take them." So if your project manager comes out with something like "A pot upturned to empty the decay. The superior one attends to the Way of Heaven.", you'll know whence he's distilling his madness. -- http://mail.python.org/mailman/listinfo/python-list
Re: How can engineers not understand source-code control?
;; This buffer is for notes you don't want to save, and for Lisp evaluation. ;; If you want to create a file, first visit that file with C-x C-f, ;; then enter the text in that file's own buffer. Cameron Laird wrote: > Well *that* certainly made my morning unpleasant. Then let's see if I can spoil you afternoon, too ... I was working on a project (that used Excel, alas) that checked the daily allocation of oil and gas. The calculations were very complicated, and liable to error. I thought it would be a good idea if I serialised intermediate calculations so they could be checked. My solution was to save them as a CSV file, with array name in the first column, index variables in subsequent columns, and array value in the last column. That way, they could be checked manually. The standard approach at my company would have been to create honking big spreadsheets to house these values. Anyway, time went on, it was decided that these daily calculations needed to be aggregated to monthly values. Well, it turned out that the solution I had adopted was quite good, because one could just suck the file in, read off the relevant variables, and populate an array. To be compared with what would normally happen of creating a nexus of links to a disk-busting collection of spreadsheets. I shall have my revenge, though. The file serve hierarchy that we have is very complicated, and is due for simplification in the very near future. So all those peeps who did spreadsheets, with hard links to other spreadsheets, are in for a bit of a surprise. I think the I-Ching expressed it better than I ever could: The bird's nest burns up. The wanderer laughs at first, Then must needs lament and weep. Through carelessness he loses his cow. Misfortune. Source: http://www.eclecticenergies.com/iching/hexagram.php?nr=56 I'm thinking that the I-Ching is a vast untapped resource for programming wisdom, plus it makes it funny. Or haikus, maybe they'd be good. -- http://mail.python.org/mailman/listinfo/python-list
Re: How can engineers not understand source-code control?
> Cameron Laird wrote: > >> I've seen the infatuation for Excel (and so on) for years, True story: when I began working for my current employer, there was a guy there doing some work with a spreadsheet. He was given two weeks to perform the task. It was a loss-leader to get some real work from the client. There already existed a spreadsheet, which did financial projections. It used VBA fairly extensively, and his task was to adapt it to remove the VBA code. This means converting things like functions into equivalent cell formulae. The rationale behind this is that VBA is too hard for most people to understand, whereas formulae are easier to understand. Conditionals look really confusing in formulae, and I don't know how he coped with loops. And then, of course, you have to replicate them to every cell that requires them. Can you imagine that? Is this very the definition of madness, or what? The whole thing was a gigantic spreadsheet (I can't remember, it was either 9Mb or 90Mb in size), and kept crashing every few minutes. Utter utter insanity. Whenever he went back the client, she demanded improvements. We had effectively told her that she could have whatever whe wanted. And oh, it would only take 2 weeks. The managers never pulled the plug on the project. Apparently, our guy sat in on a conversation that the client had with a potential contractor who would replace the spreadsheet. His first question was, surprise surprise, "why on earth did you try to do it that way?" The thing is, our guy was scheduled to be booted out the door because he was in a business area that was being discontinued by us, so from my employer's point-of-view, I guess that all this lunacy actually made sense. -- http://mail.python.org/mailman/listinfo/python-list
Re: The Industry choice
Cameron Laird wrote: > In article <[EMAIL PROTECTED]>, > Mark Carter <[EMAIL PROTECTED]> wrote: >. >[tale of *very* >typical experience >with non-software >engineers] >. >. > Don't start me! Dammit, too late ... I've noticed that they have an overwhelming obsession with GUIs, too. They design wizards for everything. Damn pretty they are, too. Albeit a bit flakey. They seem to conflate pretty interfaces with good interfaces and good software. I used to joke that since our software wasn't particularly magical, it didn't need wizards. But I think I just ended up sounding bitter. We once had a bit of software that we thought we'd like to turn into a generic application. The focus on improvements was, predictably enough, that we should design a GUI that could do anything a client would likely to want to do. It was my opinion, though, having seen the very "special-cases" nature required in the original software, that it was almost impossible to predict exactly how a customer might want the product tailored. I suggested that what they really needed was a library (Python would have been good for this, Lisp might have been even better) that could be extended as required. GUIs second, functionality first. But hey, what would I know. Fortunately, the whole thing's been put on the back burner. And trying to get through to them why source control makes sense, that when more than one person works on a project, some form of coordination is required, that copying and pasting code is evil, and that Excel probably isn't the hammer for every nail. Honestly, I thought (real) engineers were supposed to be clever. -- http://mail.python.org/mailman/listinfo/python-list
Re: The Industry choice
> It might be nice if it was widely understood (in IT) that Python was a language any competent > programmer could pick up in an afternoon I am a programmer who works for a firm of engineers, where they program in VBA, badly. I've often mentioned Python, whereupon I'm usually dismissed as a crank. One of them expressed concern that if they used Python and I left, then nobody would understand what to do. I could have countered that Python is actually quite an easy language to pick up, but what's the point. We might be doing a project which involves web-type stuff. I pointed out that if they did, they wouldn't be able to use VB/VBA, and may need to use something like Python. I didn't get a reaction from that at the time, but no doubt they'll be telling me that I'll have to make Excel work through the internet, or something. -- http://mail.python.org/mailman/listinfo/python-list
Re: Which blog tool
Premshree Pillai wrote: You can use the Blogger API to post to your Blogger account. There's a Python interface to the API -- PyBlogger -- available here: http://beetle.cbtlsl.com/archives/category/pyblogger Hey, it Just Works! I got the whole basic thing working in a few minutes. It was exactly what I was looking for. Thanks for the link. -- http://mail.python.org/mailman/listinfo/python-list
Which blog tool
I currently use python to automatically summarise a certain newsgroup daily, and post the findings that it makes. Someone has suggested that they would like a to see a blog of the posts. I wondered if there was a python tool/library that could automate the blog postings. Any ideas? Some details: * the summaries are basically just text files * I already have a blog at www.blogger.com (http://markcarterturriff.blogspot.com/), so I would like to use that if possible; although any alternative free one that I can use to achieve my objective would be OK, too. * I do have my own hosted website, which can use perl but not python; but I'd rather use a freebie blog site * the whole thing must be scriptable, because it will run daily. A GUI would therefore likely get in the way. * generating an RSS feed would be nice -- http://mail.python.org/mailman/listinfo/python-list
