Python Forum

Hi there, I am having some trouble with list manipulation and was hoping someone could help me. I have no problem reading in a text file as a list using filename.readlines(). However, I am having some trouble with searching through this list to display the elements that I want. I have a text file with this general format: ...

I can't break out of the for loop in this example: ------ import sys lst = for line in sys.stdin: lst.append(line) break

Please check for sanity and approve for posting at python-dev. In Visual Basic there is the keyword "with" which allows an object- name to be declared as governing the following statements. For example: with quitCommandButton .enabled = true .default = true end with

Hello, after reading some of the book Programming Python it seems that python is something I would like to delve deeper into. The only thing is, I have no idea what I should try and write. So I was hoping that someone here could help point me to a group/project that would be a good starting place for a person with limited python knowledge, but...

Some faster Python implementations are under development. JPython has been around for a while, and PyPy and ShedSkin continue to move forward. It's worth thinking about what slows down Python implementations. It isn't the dynamism, really. As others have pointed out in the Python literature, most of the time, the more elaborate dynamic...

Hi all! I am pretty sure this has been asked a couple of times, but I don't seem to find it on the archives (Google seems to have a couple of problems lately). I am wondering what is the most pythonic way of dealing with missing keys and default values. According to my readings one can take the following approaches:

Hi, I am wondering how do I 'flatten' a list or a tuple? For example, I'd like to transform or ] to . Another question is how do I pass a tuple or list of all the aurgements of a function to the function. For example, I have all the arguments of a function in a tuple a=(1,2,3). Then I want to pass each item in the tuple to a function f...

Hi, I have read the source code of the built-in random module, random.py. After also reading Wiki article on Knuth Shuffle algorithm, I wonder if the shuffle method implemented in random.py produces results with modulo bias. The reasoning is as follows: Because the method random() only produces finitely many possible results, we get...

I'm pretty new to python, but am very happy with it. As well as using it at work I've been using it to solve various puzzles on the Project Euler site - http://projecteuler.net. So far it has not let me down, but it has proved surprisingly slow on one puzzle. The puzzle is: p is the perimeter of a right angle triangle with integral length...

Python has had the Decimal data type for some time now. The Decimal data type is ideal for financial calculations. Using this data type would be more intuitive to computer novices than float as its rounding behaviour matches more closely what humans expect. More to the point: 0.1 and 0.01 are exact in Decimal and not exact in float. ...

Had a unsettling conversation with a CS instructor that teaches at local high schools and the community college. This person is a long-term Linux/C/Python programmer, but he claims that the install, config, and library models for C# have proved to be less problematic than Python. So both his courses (intro, data structs, algorithms) are...

I mean, all the class instances that equal to each other should be reduced into only one instance, which means for instances of this class there's no difference between a is b and a==b. Thank you.

I'm a Java guy who's been doing Python for a month now and I'm convinced that 1) a multi-paradigm language is inherently better than a mono-paradigm language 2) Python writes like a talented figure skater skates. Would you Python old-timers try to agree on a word or two that completes:

I'm new to Python, and OOP. I've read most of Mark Lutz's book and more online and can write simple modules, but I still don't get when __init__ needs to be used as opposed to creating a class instance by assignment. For some strange reason the literature seems to take this for granted. I'd appreciate any pointers or links that can help...

I want to prevent some process from running. The code is in the following. I encounter some unexpected troubles. Probelm1: This program cannot terminate "scrcons.exe" and "FNPLicensingService.exe",which are system processes. Problem2:After a while, this program will abort by error File "C:\Python25\lib\wmi.py", line 397, in __call__...

Hi. I wondered if anyone knew the rationale behind the naming of the Popen class in the subprocess module. Popen sounds like the a suitable name for a function that created a subprocess, but the object itself is a subprocess, not a "popen". It seems that it would be more accurate to just name the class Subprocess, can anyone explain why this...

Hi, after hearing a lot about decorators and never actually using one I have decided to give it a try. My particular usecase is that I have class that acts as a proxy to other classes (i.e. passes messages along to those classes) however hand-coding this type of class is rather tedious, so I decided to use decorator for that. Can somebody...

I'm parsing some text files, and I want to strip blank lines in the process. Is there a simpler way to do this than what I have here? lines = filter(lambda line: len(line.strip()) 0, lines) Thomas

I have some old Common Lisp functions I'd like to rewrite in Python (I'm still new to Python), and one thing I miss is not having to declare local variables. For example, I have this Lisp function: (defun random-char () "Generate a random char from one of " (if (< 50 (random 100)) (code-char (+ (random 10) 48)) ; ascii 48 = 0

PEP315 (Enhanced while loop) suggests a syntax as follows... do: ... while condition: ... The motives are IMO good, but I don't like this solution. It replicates a problem with the C do loop (even though this is actually different to the C do loop).

Here I send it. Suggestions and all kinds of recomendations are more than welcomed. If it all goes ok, it'll be a PEP when I finish writing the code. Thank you. .. Facundo

Does anyone know how i can fix my Palindrome program? s = raw_input('Enter a String: ') punctuation = '%$!*.,-:? ;()\'\"\\' i = 0 h = 0 t = 0 p = '' z = 0 while s!= ' ':

Hi, Does anybody know where this term comes from? "First-class object" means "something passable as an argument in a function call", but I fail to see the connection with "object class" or with "first-class airplane ticket". I just find the name a bit strange. Also, if there are first-class objects, what would the second-class objects or...

Hi, I have the following inter-class relationships: __main__: (in file LMCMain.py) imports module FileIO defines class LMCMain instanciats main = LMCMain(...) FileIO.py:

PEP 315 suggests that a statement such as do: x = foo() while x != 0: bar(x) be equivalent to while True: