[Tutor] __init__.py not working?
Hello, In my script library, one directory is named rendering. When I try to import a module from this directory, I always get this error: #ImportError: dynamic module does not define init function (initrendering) However, there is an __init__.py file in there, and also the pyc version. All other directories of the library seem to be working fine. Any suggestion? Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] compiling python files
That would be the compileall utility: http://www.python.org/doc/2.4.1/lib/module-compileall.html Cheers Bernard On 7/1/05, Johan Geldenhuys [EMAIL PROTECTED] wrote: Hi all, I have python .py files that I want to compile into .pyc files. Is there a easy way of doing this? Thanks, Johan ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] repr()
Hello, Possibly I am missing something, but how do you use the repr() function? I type this ultra-simple function: def myFunc(): print 'hello' Then run repr( myFunc ) Wich returns 'function myFunc at 0x009C6630' Okay then I run s = repr( myFunc() ) print s Wich returns 'None' Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] repr()
Ok thanks a lot. The real question is, then, is there a way I can print the code of a function as a string? Something like 'def myFunction: print hello' Thanks Bernard On 6/7/05, Max Noel [EMAIL PROTECTED] wrote: On Jun 7, 2005, at 20:42, Bernard Lebel wrote: repr( myFunc ) Wich returns 'function myFunc at 0x009C6630' Okay then I run s = repr( myFunc() ) print s Wich returns 'None' That's perfectly normal. Your last assignment calls the function, then assigns to s the representation of the function's return value. A function that doesn't have a return statement returns None, and repr(None) == 'None'. Which is what you get. -- Max maxnoel_fr at yahoo dot fr -- ICQ #85274019 Look at you hacker... A pathetic creature of meat and bone, panting and sweating as you run through my corridors... How can you challenge a perfect, immortal machine? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] repr()
Well, to make a long story short, this is because I use Python through another software, Softimage|XSI, and by design a string is required to pass logic to on-the-fly GUIs. Since XSI implements 3 other languages (ActivePerl, VBScript and JScript), I suppose this was designed that way with JScript's .toString() in mind. The SDK documentation does indeed show only a JScript example. Bernard Alan G wrote Curious as to why you would ever want to though? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] dictionary values in strings
Indeed, dictionaries don't have a .key attribute.
Instead, use:
# Get list of values for 'key1'
aList = dol[ 'key1' ]
This would return the list of values you have assigned to 'key1' in
the dictionary. Once you got that list, you can look in the list to
find out the index of 'lil1' and return it:
# Iterate list of values assigned to 'key1'
for i in range( 0, len( dol[ 'key1' ] ) ):
# Get list element using current iteration value
sValue = dol[ 'key1' ][i]
# If list element is 'lil1', print its list index
if sValue == 'lil1': print 'lil1 has index : ' + str( i )
Cheers
Bernard
On 5/19/05, William O'Higgins [EMAIL PROTECTED] wrote:
I am trying to discover the syntax for call on a dictionary of lists by
key and index.
The data structure looks like this:
dol = {'key1':['li1','li2','li3'],'key2':['li1','li2','li3'],\
'key3':['li1'li2,'li3','']}
The keys are passed to a function as arguments, and I want the value of
the specified list index. This is what I *thought* it would look like:
dol.key(argument)[0] # would return li1 when argument equals key1
But that's wrong. The error I get is this:
AttributeError: 'dict' object has no attribute 'key'
I don't know how to interpret that error (well, I know I screwed up, but
... :-) Thanks.
--
yours,
William
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Re: [Tutor] map() and lambda to change class instance attribute (fwd)
Well, that was a nice explanation. Thanks once again Kent! Bernard On 5/16/05, Kent Johnson [EMAIL PROTECTED] wrote: Bernard Lebel wrote: Hi Kent, So if I undestand you right, mapping a function with map() when it is a built-in function will/may be faster than a for loop, but if it's a custom function (ie. a def one), it will most likely be slower? I guess I didn't proofread that last mail...what I meant is - Write the code for clarity first - If you find a performance bottleneck then test different solutions to see which is fastest for your actual data and usage. - Mapping a builtin function over a list is relatively fast in Python and it is worth trying if it meets your needs. - Calling a function is relatively expensive in Python so if using map() requires you to define a helper that may wipe out its advantage. - Testing is crucial! Guessing is only good for helping to come up with ideas to test. Here is a program that tests six ways to apply a function to elements of a list. The functions don't create new lists except as side effects since that was the original problem. They use map(), list comprehension and an explicit for loop to apply str() or a Python function returning str() to the elements of a list. (The list already contains strings so the actual function call should be fast.) import timeit data = [str(n) for n in range(100)] def strByMap(): map(str, data) def strByListComp(): [str(n) for n in data] def strByLoop(): for n in data: str(n) def func(x): return str(x) def funcByMap(): map(func, data) def funcByListComp(): [func(n) for n in data] def funcByLoop(): for n in data: func(n) def timeOne(fn): setup = from __main__ import + fn.__name__ stmt = '%s()' % (fn.__name__) t = timeit.Timer(stmt, setup) secs = min(t.repeat(number=1000)) print '%15s %s' % (fn.__name__, secs) for fn in [ strByMap, strByListComp, strByLoop, funcByMap, funcByListComp, funcByLoop ]: timeOne(fn) ### Here are the results on my computer: strByMap 0.0359623918682 strByListComp 0.0581065470611 strByLoop 0.0481150537289 funcByMap 0.0810943849009 funcByListComp 0.0891375859222 funcByLoop 0.0806144356336 So for this test, map is fastest when calling a builtin and explicit looping is fastest when calling a function. With the explicit loop you might be able to inline the function, in which case it would be much faster than either map or list comp. Modifying the program slightly so that each function actually creates a list changes the results dramatically: strByMap 0.0365733633744 strByListComp 0.0579948010152 strByLoop 0.0764722890758 funcByMap 0.0811885309446 funcByListComp 0.0883995032888 funcByLoop 0.10586876265 Now map() is fastest in both cases, though a for loop with inlined code beats map() with an external function. Kent Thanks Bernard On 5/13/05, Kent Johnson [EMAIL PROTECTED] wrote: Bernard Lebel wrote: The authors even go as far as saysing, on page 228 (first paragraph) that map() used that way has a performance benefit and is faster than a for loop. That may well be correct, at least in the case where the function passed to map is a builtin. Mapping a builtin to over a list is extremely fast. So write the code with a for loop so it is clear. When you identify a performance bottleneck you can try rewriting your loop using map or list comprehension, which is also fast. Until then it is premature optimization. For typical loops over a small number of items I can't imagine you would notice the difference. Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] map() and lambda to change class instance attribute (fwd)
That is very interesting John. Thanks! Bernard On 5/19/05, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Quoting Bernard Lebel [EMAIL PROTECTED]: Well, that was a nice explanation. Thanks once again Kent! There is a nice (not too technical) essay on the running speeds of different looping constructs on python.org: http://www.python.org/doc/essays/list2str.html Just FYI :-) -- John. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Finding word in file
Hi Joseph, To answer your last question first, you should use the os.path.exsits() method to see if the path is valid: http://www.python.org/doc/2.4.1/lib/module-os.path.html As for finding a word in a text, I would suggest to write a basic text parser that would work on small files. def parseText(): # oFile: text file to test # myWord: word we are looking for # Get all lines into list aLines = oFile.readlines() # Perform list comprehension on lines to test if the word is found for sLine in aLines: # Parse the line (remove spaces), returns list aLine = sLine.split() # Iterate words and test to see if they match our word for sWord in aLines: # if it matches, append it to our list if sWord == myWord: aWords.append( sWord ) # Create empty list to store all instances of the word that we may find aWords = [] # Prompt user to know what word to search myWord = str( raw_input( 'what word to searh:' ) ) Note that I'm still new to Python, there might be more efficient ways to do that. For larger text files (in the order of thousands of lines), you may not use readlines() to build a list of the lines and insteand read one line after another with readline() or xreadline() and append to the list as you find the word. Cheers Bernard On 5/18/05, Joseph Quigley [EMAIL PROTECTED] wrote: I'm making a program that opens a file and tries to find the word you specify. I can't get it to find the word! I also would like to know how I can get it to print 2 lines above and 2 lines below the line with the word specified. One more thing, the try: IOError won't work... I type the name of a nonexistent file and the except won't kick in and print my error message! Not to mention the program is killed. How can i fix that? Thanks, JQ Full Code: while True: file_name = raw_input(Enter the full file name: ) f = file(file_name, 'r') try: IOError except: print File not found. Directories are not supported while True: line = f.readline() if len(line) == 0: break find_word = raw_input(What word do you want to find (quit() to quit)?\n ) if find_word in file_name: print f.readline(find_word) elif find_word == quit(): break print line, f.close() close = raw_input(\n\nQuit program? (Y/N) ) if ((close == Y) or (y == close)): break else: print ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Finding word in file
Ooops, a part of my code was missing, sorry about that. Here is it again, complete. def parseText(): # oFile: text file to test # myWord: word we are looking for # Get all lines into list aLines = oFile.readlines() # Perform list comprehension on lines to test if the word is found for sLine in aLines: # Parse the line (remove spaces), returns list aLine = sLine.split() # Iterate words and test to see if they match our word for sWord in aLines: # if it matches, append it to our list if sWord == myWord: aWords.append( sWord ) # Create empty list to store all instances of the word that we may find aWords = [] # Prompt user to know what word to search myWord = str( raw_input( 'what word to searh:' ) ) # Call function parseText() # Check if list has at least one element if len( aWords ) 1: print 'Word not found in file' else: print str( len( aWords ) ) + ' instances of our word found in file' Sorry again Bernard On 5/18/05, Bernard Lebel [EMAIL PROTECTED] wrote: Hi Joseph, To answer your last question first, you should use the os.path.exsits() method to see if the path is valid: http://www.python.org/doc/2.4.1/lib/module-os.path.html As for finding a word in a text, I would suggest to write a basic text parser that would work on small files. def parseText(): # oFile: text file to test # myWord: word we are looking for # Get all lines into list aLines = oFile.readlines() # Perform list comprehension on lines to test if the word is found for sLine in aLines: # Parse the line (remove spaces), returns list aLine = sLine.split() # Iterate words and test to see if they match our word for sWord in aLines: # if it matches, append it to our list if sWord == myWord: aWords.append( sWord ) # Create empty list to store all instances of the word that we may find aWords = [] # Prompt user to know what word to search myWord = str( raw_input( 'what word to searh:' ) ) Note that I'm still new to Python, there might be more efficient ways to do that. For larger text files (in the order of thousands of lines), you may not use readlines() to build a list of the lines and insteand read one line after another with readline() or xreadline() and append to the list as you find the word. Cheers Bernard On 5/18/05, Joseph Quigley [EMAIL PROTECTED] wrote: I'm making a program that opens a file and tries to find the word you specify. I can't get it to find the word! I also would like to know how I can get it to print 2 lines above and 2 lines below the line with the word specified. One more thing, the try: IOError won't work... I type the name of a nonexistent file and the except won't kick in and print my error message! Not to mention the program is killed. How can i fix that? Thanks, JQ Full Code: while True: file_name = raw_input(Enter the full file name: ) f = file(file_name, 'r') try: IOError except: print File not found. Directories are not supported while True: line = f.readline() if len(line) == 0: break find_word = raw_input(What word do you want to find (quit() to quit)?\n ) if find_word in file_name: print f.readline(find_word) elif find_word == quit(): break print line, f.close() close = raw_input(\n\nQuit program? (Y/N) ) if ((close == Y) or (y == close)): break else: print ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Lists of files
Hi William,
First, check out the os and os.path modules. It has exactly what you
need to handle files and directories.
http://www.python.org/doc/2.4.1/lib/module-os.html
More specifically:
http://www.python.org/doc/2.4.1/lib/os-file-dir.html
http://www.python.org/doc/2.4.1/lib/module-os.path.html
import os
# Get list of files in directory
aFiles = os.listdir( path to files )
# Create empty list to store image files
aImgFiles = []
# Iterate list to collect image files
for sFile in aFiles:
# Split extension to see if it is an image type
# This returns a list of two elements, check the last one to get
the extension
if os.path.splitext( sFile )[-1] == animageextension:
aImgFiles.append( sFile )
You could also do that more quickly with list comprehension:
aImgFiles = [ sFile for sFile in os.listdir( pathtolistfiles ) if
os.path.splitext( sFile )[-1] == imageextension ]
Cheers
Bernard
On 5/14/05, William O'Higgins [EMAIL PROTECTED] wrote:
Here's the problem - I want a list (array) of the files in a directory,
and then I want to iterate over the list testing for image-ness (with
imghdr.what()) and put all the image filenames in a global list.
What I've tried is this:
files = glob.glob('*.*')
for file in files:
global pics
pics = []
if imghdr.what(file):
# so far so good - file is a list of files in the directory
pics.append(file)
# I this this is the problem - my list only has the last
# alphabetical entry in it
So there's two questions - is there a better way to create a list of
files in a directory? And, how do I populate my list to get all of the
filenames. I've also tried pics + [file], but that gave me an empty
list.
--
yours,
William
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Re: [Tutor] map() and lambda to change class instance attribute (fwd)
Thanks Alan, that clears things up quite well. Bernard On 5/14/05, Alan Gauld [EMAIL PROTECTED] wrote: So if I undestand you right, mapping a function with map() when it is a built-in function will/may be faster than a for loop, but if it's a custom function (ie. a def one), it will most likely be slower? That's right, a builtin function, including map itself will be written in C and so be 'fast'. So we have the trade off between a Python for loop calling a function or a C loop which additionally has to build a list result. But in the builtin case we have C code calling C code which is much faster than Python code calling C code. So for a function written in Python there will be less difference and the bulk of the time is likely to be spent in the function calls but for builtins C to C could give a significant benefit. Which is faster will depend on several other factors including what the function returns and how easily that can be packaged into a list. From my personal experience I wouldn't expect map to be much faster than a for loop, if at all. But as Kent says you can always profile it and test it if you really need speed. The real issue is the map call is more obscure than an explicit loop since map() is intended to build a list not modify an existing list! Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Why use apply()?
All right, thank you. Bernard On 5/12/05, Bob Gailer [EMAIL PROTECTED] wrote: At 02:17 PM 5/12/2005, Bernard Lebel wrote: Just a generic question: why one would use apply()? In Learning Python, on page 357, there is an example of generating an instance using apply(): class A: def __init__( self, number ): self.number = number a = apply( A, 3 ) What is the benefit of doing this over simply creating an instance the usual way: a = A( 3 ) No benefit. See 2.2 Non-essential Built-in Functions in the Python Library Reference. 'Use of apply() is not necessary since the ``extended call syntax,'' as used in the last example, is completely equivalent. Bob Gailer mailto:[EMAIL PROTECTED] 510 558 3275 home 720 938 2625 cell ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] map() and lambda to change class instance attribute (fwd)
The authors even go as far as saysing, on page 228 (first paragraph) that map() used that way has a performance benefit and is faster than a for loop. Cheers Bernard On 5/13/05, Alan Gauld [EMAIL PROTECTED] wrote: How bizarre. I'm astonished that Lutz/Ascher even show that as a means of changing an attribute. As Danny said, it's definitely an abuse of map, and there is no advantage whatsoever, as far as I can see. In fact I suspect that it's actually slower than an explicit loop (because of the extra list building). However I was looking into lambdas in hope to eliminate the need to define a function. And a loop also avoids the need for a function, and therefore for a function call, which is another reason the map should be slower. Its completely weird that a text book should even suggest that map be used for this! Alan G Author of the Learn to Program web tutor http://www.freenetpages.co.uk/hp/alan.gauld ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] map() and lambda to change class instance attribute (fwd)
Hi Kent, So if I undestand you right, mapping a function with map() when it is a built-in function will/may be faster than a for loop, but if it's a custom function (ie. a def one), it will most likely be slower? Thanks Bernard On 5/13/05, Kent Johnson [EMAIL PROTECTED] wrote: Bernard Lebel wrote: The authors even go as far as saysing, on page 228 (first paragraph) that map() used that way has a performance benefit and is faster than a for loop. That may well be correct, at least in the case where the function passed to map is a builtin. Mapping a builtin to over a list is extremely fast. So write the code with a for loop so it is clear. When you identify a performance bottleneck you can try rewriting your loop using map or list comprehension, which is also fast. Until then it is premature optimization. For typical loops over a small number of items I can't imagine you would notice the difference. Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Why use apply()?
Just a generic question: why one would use apply()? In Learning Python, on page 357, there is an example of generating an instance using apply(): class A: def __init__( self, number ): self.number = number a = apply( A, 3 ) What is the benefit of doing this over simply creating an instance the usual way: a = A( 3 ) Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] map() and lambda to change class instance attribute
Hello, Let say I have several class instances in a list, and these class instances have an attribute named value, whose value is an integer. I would like to know if it is possible to loop over the list of instances to change their value attribute, using a map( ( lambda:...), ... ) type of loop. I'm very new to lambdas as you can see :-) Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] map() and lambda to change class instance attribute
Hi Danny, Thanks for the answer. I have to confess that I already use map(), or should I say abuse, for this, although it is the first time I consider using lambdas. Up until now I always used map() to perform a looped call on a function that would change the attribute value, as shown in Mark Lutz David Ascher's Learning Python: # Perform attribute value change on a single instance def iterateInstances( oInstance ): oInstance.value = myValue # Loop over list of instances map( iterateInstances, aListOfInstances ) However I was looking into lambdas in hope to eliminate the need to define a function. Cheers On 5/11/05, Danny Yoo [EMAIL PROTECTED] wrote: On Wed, 11 May 2005, Bernard Lebel wrote: Let say I have several class instances in a list, and these class instances have an attribute named value, whose value is an integer. I would like to know if it is possible to loop over the list of instances to change their value attribute, using a map( ( lambda:...), ... ) type of loop. Hi Bernard, Hmmm... then map() is probably not what you want. map() is meant to transform a list of things into another list of things, but isn't really meant to mutate its input. It is possible to abuse map() to do what you're trying to do, using the setattr() function: ## Pseudocode map(lambda instance: setattr(instance, 'value', 42)) ## but this is definitely language abuse. *grin* map() is not intended to be run just to affect changing assignments on its input. It'll probably be clearest in Python just to write out the loop explicitely. Best of wishes to you! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Else in list comprehension
Hello, I just started using list comprehensions (loving them!) I know you can add an if statement, but can you put in there an else? I could not find an example of this. Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Appending to many lists with list comprehension
Hello, I have an object, and this object has attributes. These attributes are objects in their own right, and each attribute also have its own attributes. So I loop over the top object, and for each attribute encountered, I want to put in a list two of the attributes of this attribute. Hope it makes sense. Right now, here is what I'm doing: aList = [ [], [] ] # Iterate attributes of the top object for oAttribute in oObj.attributes: # Append to list 0 the attribute type of the current attribute aList[0].append( str(oAttribute.type) ) # Append to list 1 the attribute name of the current attribute aList[1].append( str(oAttribute.name) ) Instead of having two separate lists and a for loop, I'd like to perform a list comprehension that would do this all in one go, if this is doable. Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Dynamically composing a module name
Hi, The one thing I would try, if I understand what you're after correctly, would be to run a exec command with the module name. modulename = 'myModule' exec 'import ' + modulename Then you can access the module names as any imported module. Cheers Bernard On 4/19/05, Tim Johnson [EMAIL PROTECTED] wrote: Hello Pythonmeisters: Is it possible to dynamically compose a module name for import? Pointers to documentation or other discussions would be sufficient at this time. thanks -- Tim Johnson [EMAIL PROTECTED] http://www.alaska-internet-solutions.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Re: Class - superclass
Thanks a lot, now it's clear. Bernard On Apr 8, 2005 3:48 PM, Andrei [EMAIL PROTECTED] wrote: Bernard Lebel wrote on Fri, 8 Apr 2005 15:05:13 -0400: I'm experimenting with basic inheritance concepts, and something that I would assume to work returns an error. class A: ... def __init__( self ): ... self.a = 13 ... class B( A ): # create sub-class of class A ... def __init__( self ): ... self.b = 14 Call the __init__ of the ancestor explicitly: class B(A): ... def __init__(self): ... A.__init__(self) ... self.b = 14 b = B() b.a, b.b (13, 14) B inherits everything from A, but by defining B.__init__, the __init__ inherited from A is replaced, so you'll need to call it explicitly. Python has no way of knowing that you still want to use the original __init__ too unless you tell it so. To demonstrate the fact that __init__ is indeed inherited: class C(A): ... pass c = C() # inherited __init__ (A.__init__) is called c.a 13 -- Yours, Andrei = Real contact info (decode with rot13): [EMAIL PROTECTED] Fcnz-serr! Cyrnfr qb abg hfr va choyvp cbfgf. V ernq gur yvfg, fb gurer'f ab arrq gb PP. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Class - superclass
Hello, I'm experimenting with basic inheritance concepts, and something that I would assume to work returns an error. class A: ... def __init__( self ): ... self.a = 13 ... class B( A ): # create sub-class of class A ... def __init__( self ): ... self.b = 14 ... b = B() # create instance of class B b.a # here I would expect the class A's a attibute to be accessible... Traceback (most recent call last): File stdin, line 1, in ? AttributeError: B instance has no attribute 'a' Anyone can shed any light on this? Using Python 2.3.4. Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] [HELP]how to test properties of a file
As far as I'm aware, this is very normal. The file is being used by an
application, so there is a lock on it.
Cheers
Bernard
On Apr 4, 2005 7:34 PM, Shidai Liu [EMAIL PROTECTED] wrote:
I found out in the following situation, it fails to work.
Say, 'somefile.csv' is opened by EXCEL,
os.access('somefile.csv', os.W_OK)
True
file('somefile.csv', 'w')
IOError: [Errno 13] Permission denied: 'somefile.csv'
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[Tutor] test
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Re: [Tutor] What is the best book to start?
Hoffmann wrote: Hi All, I am starting to studying Python. I have some previous experience with C (beginner level). Could, anyone, please, suggest a good Python book? I have both Learning Python by Lutz Ascher, and Python How to Program by Deitel and others. Are those good books? Thanks. Hoffmann I have only the former, and am totally happy with it. Very clear and well put book. A great investment. Cheers Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Basic terminology
Well, thanks everyone who answered, much clearer now. Bernard Max Noel wrote: In a slightly more generic fashion (everybody started dropping examples), the goal of an integer (euclidian) division (say, a / b) is to express an integer as such: a = b * quotient + remainder Where all the numbers used are integers, and 0 = remainder b. When you perform integer division in Python, a / b (a // b in 2.4+) gives you the quotient, and a % b gives you the remainder. See the other posts for examples of use :p -- Max maxnoel_fr at yahoo dot fr -- ICQ #85274019 Look at you hacker... A pathetic creature of meat and bone, panting and sweating as you run through my corridors... How can you challenge a perfect, immortal machine? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Queued threads
Hello, I have already messed a little with simple thread programming, wich took this form: from threading import Thread def mainFunction(): pass Thread( target=mainFunction ).start() Now, I have a list of jobs, each job being a windows bat file that launches an executable and performs a rendering task. So I have this queue of jobs, and would like to launch one only when the previous one has finished, and in a separate window. So far I have not been having much success with simple stuff: from threading import Thread def mainFunction(): print 'function print' return 1 for i in range( 0, 3 ): oThread = Thread( target=mainFunction ).start() if oThread == 1: print 'sleeping 3 seconds' time.sleep( 3 ) In this example, 'sleeping 3 seconds' not returned, and each thread is started without any waiting. I'm looking at the various threading module details in the library but I have to admit that, well, I'm a bit at loss here. Thanks in advance Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Queued threads
That is an attempt to catch the death of the thread. I guess I'm not taking the right steps ;-) Bernard Liam Clarke wrote: I'm sorry, but when does oThread get the value 1? If you're testing for it's existence via a True/False thing, try if oThread: But otherwise, I'm not sure what you're expecting to get. On Tue, 15 Feb 2005 20:58:15 -0500, Bernard Lebel [EMAIL PROTECTED] wrote: Hello, I have already messed a little with simple thread programming, wich took this form: from threading import Thread def mainFunction(): pass Thread( target=mainFunction ).start() Now, I have a list of jobs, each job being a windows bat file that launches an executable and performs a rendering task. So I have this queue of jobs, and would like to launch one only when the previous one has finished, and in a separate window. So far I have not been having much success with simple stuff: from threading import Thread def mainFunction(): print 'function print' return 1 for i in range( 0, 3 ): oThread = Thread( target=mainFunction ).start() if oThread == 1: print 'sleeping 3 seconds' time.sleep( 3 ) In this example, 'sleeping 3 seconds' not returned, and each thread is started without any waiting. I'm looking at the various threading module details in the library but I have to admit that, well, I'm a bit at loss here. Thanks in advance Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] calling an external program
The os module is the answer. Use chdir() to make the target executable's directory the current directory, and then os.system( 'command' ) to run the actual command. Cheers Bernard Lobster wrote: - I am trying to call up an external program with something like a Shell command - can not find a way of doing this (in windows) Any hints? Ed Jason ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] How to run a script file
Thanks everyone who answered, it's sorted now :-D Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Basic question - How to use a class from a file?
Hello, An easy one to start the year. Trying to write my first class, already running into problems after 3 lines! :-( So have this little class: class rt: def walk(self): print 'yeah' So if I write this in the Python shell, instantiate rt and call walk(), I get the proper result. yeah gets printed. Now let say I put this into a file. I want to import that class and use its methods, but this is were I get lost. import rt rt.walk() Returns: Traceback (most recent call last): File interactive input, line 1, in ? AttributeError: 'module' object has no attribute 'walk' When I try to instantiate the class, I get an non-callable module object error. So how to use a class from a file? Thanks Bernard ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
