Re: lambda in list comprehension acting funny

Hi. funcs = [ lambda x: x**i for i in range( 5 ) ] print funcs[0]( 2 ) This gives me 16 When I was excepting 1 Does anyone know why? Just the way Python lambda expressions bind their variable references. Inner 'i' references the outer scope's 'i' variable and not its value 'at the tim

Re: lambda in list comprehension acting funny

>>> funcs = [ lambda x: x**i for i in range( 5 ) ] >>> print funcs[0]( 2 ) >>> >>> This gives me >>> 16 >>> >>> When I was excepting >>> 1 >>> >>> Does anyone know why? > >Just the way Python lambda expressions bind their variable > references. Inner 'i' references the outer scope's 'i' variabl

Re: Tkinter.event.widget: handler gets name instead of widget.

On Tue, 2012-07-10 at 18:06 -0700, Rick Johnson wrote: > Also: > > Q3: Why are you explicitly setting the name of your "subFrame" widgets > instead of allowing Tkinter to assign a unique name?...AND are you > aware of the conflicts that can arise from such changes[1]? > I find custom-named widge

introduction and first question about multithreading

Greetings, My name is Vojta and I am blind student. I am slowly learning Python for about 4 years and I like it alot, mostly its ability to run on various platforms. My primary system is Ubuntu 12.04, but I have Windows XP at hand. I am using python 2.7. I have learned basics from the book A byte o

Re: lambda in list comprehension acting funny

On 11/07/2012 2:41 AM, Daniel Fetchinson wrote: funcs = [ lambda x: x**i for i in range( 5 ) ] print funcs[0]( 2 ) print funcs[1]( 2 ) print funcs[2]( 2 ) This gives me 16 16 16 When I was excepting 1 2 4 Does anyone know why? Cheers, Daniel I don't understand why you would expect 1, 2,

Re: introduction and first question about multithreading

In article , Vojt®ßch Pol®¢‰ek wrote: > Then the menu module kicks in and should launch its > own loop checking for pygame keyboard events, but right after doing it > it prints: > [xcb] Unknown sequence number while processing queue > [xcb] Most likely this is a multi-threaded client and X

ANN: PollyReports 1.5 -- Band-oriented PDF Report Generator

I've held off announcing this until I was sure it was really stable; it's been 19 days since I made the last change to it, so here goes. PollyReports is my Python module for report generation. It is designed to be, quite literally, the "simplest thing that can possibly work" in the field of PDF

[newbie] Python and Qt4 Designer

I'm trying to combine python-code made with QT4 designer with plain python statements like file = open("test","w") Can anyone tell me what I have to add to the following code just to open a file when clicking on the load-button and closing it by clicking on the save button. #!/usr/bin/env python

Re: lambda in list comprehension acting funny

On Wed, Jul 11, 2012 at 4:28 AM, Colin J. Williams wrote: > I don't understand why you would expect 1, 2, 4. Because: funcs[0](2) == 2 ** 0 == 1 funcs[1](2) == 2 ** 1 == 2 funcs[2](2) == 2 ** 2 == 4 > Perhaps parentheses will help the order of evaluation: > > funcs = [(lambda x: x**i) for i in

Re: Opening multiple Files in Different Encoding

On Tuesday, July 10, 2012 11:16:08 PM UTC+5:30, Subhabrata wrote: > Dear Group, > > I kept a good number of files in a folder. Now I want to read all of > them. They are in different formats and different encoding. Using > listdir/glob.glob I am able to find the list but how to open/read or > proc

Re: lambda in list comprehension acting funny

Exactly. It's threads like these which remind me why I never use lambda. I would rather give a function an explicit name and adhere to the familiar Python syntax, despite the two extra lines of code. I don't even like the name "lambda". It doesn't tell you what it is (unless you're John McCa

Re: Opening multiple Files in Different Encoding

On 11 July 2012 19:15, wrote: > On Tuesday, July 10, 2012 11:16:08 PM UTC+5:30, Subhabrata wrote: > > Dear Group, > > > > I kept a good number of files in a folder. Now I want to read all of > > them. They are in different formats and different encoding. Using > > listdir/glob.glob I am able to f

Re: lambda in list comprehension acting funny

On 11/07/12 20:38:18, woooee wrote: > You should not be using lambda in this case > .for x in [2, 3]: > .funcs = [x**ctr for ctr in range( 5 )] > .for p in range(5): > .print x, funcs[p] > .print The list is called "funcs" because it is meant to contain functions. Your code doe

Re: Opening multiple Files in Different Encoding

On Wed, 11 Jul 2012 11:15:02 -0700, subhabangalore wrote: > On Tuesday, July 10, 2012 11:16:08 PM UTC+5:30, Subhabrata wrote: >> Dear Group, >> >> I kept a good number of files in a folder. Now I want to read all of >> them. They are in different formats and different encoding. Using >> listdir/g

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 11:38:18 -0700, woooee wrote: > You should not be using lambda in this case > .for x in [2, 3]: > .funcs = [x**ctr for ctr in range( 5 )] > .for p in range(5): > .print x, funcs[p] > .print If you change the requirements, it's always easy to solve problem

Re: ANN: PollyReports 1.5 -- Band-oriented PDF Report Generator

On 12/07/12 00:06, Chris Gonnerman wrote: I've held off announcing this until I was sure it was really stable; it's been 19 days since I made the last change to it, so here goes. PollyReports is my Python module for report generation. It is designed to be, quite literally, the "simplest thing tha

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 13:21:34 -0700, John Ladasky wrote: > Exactly. It's threads like these which remind me why I never use > lambda. I would rather give a function an explicit name and adhere to > the familiar Python syntax, despite the two extra lines of code. lambda is familiar Python syntax,

Re: [newbie] Python and Qt4 Designer

On 11/07/12 17:37, Jean Dubois wrote: > I'm trying to combine python-code made with QT4 designer with plain > python statements like > file = open("test","w") > Can anyone tell me what I have to add to the following code just to > open a file when clicking on the load-button and closing it by > cl

Automatic setup of meta path hooks?

Hi, I'm working on a meta path hook that performs compilation of C extension modules on import ( github.com/jwp/py-c ; pip install c ). It mostly works, but I'm having a hard time finding a standard way to automatically install the hook upon interpreter startup. I've thought about just having

Re: lambda in list comprehension acting funny

>> You should not be using lambda in this case >> .for x in [2, 3]: >> .funcs = [x**ctr for ctr in range( 5 )] >> .for p in range(5): >> .print x, funcs[p] >> .print > > If you change the requirements, it's always easy to solve problems. But > it is the wrong problem that you ha

ANN: Zeus - Windows IDE for Python

The latest Zeus IDE Version 3.97o is now available: http://www.zeusedit.com/python.html This latest Zeus release adds improved Python debugger support. Other Pyhon language features include syntax highlighting, code completion, smart indenting, class browsing and code folding. Zeus is also

Re: lambda in list comprehension acting funny

On Thursday, July 12, 2012 12:34:33 AM UTC+8, Ian wrote: > On Wed, Jul 11, 2012 at 4:28 AM, Colin J. Williams wrote: > > I don't understand why you would expect 1, 2, 4. > > Because: > > funcs[0](2) == 2 ** 0 == 1 > funcs[1](2) == 2 ** 1 == 2 > funcs[2](2) == 2 ** 2 == 4 > > > Perh

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 21:05:30 -0400, Dennis Lee Bieber wrote: > {non sequitur: I still recall my archaic C++ class with the OOAD > assignment of designing said calculator -- we never had to implement > one, just design the basic classes/methods/attributes [on 3x5 cards] for > a four-banger. I manag

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 20:39:45 -0700, 8 Dihedral wrote: > I'll contribute my way of python programming: > > def powerb(x, b): # > return x**b Here's a shorter version: py> pow > One functor is enough! Nothing we have been discussing in this thread has been a functor, either in the

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 08:41:57 +0200, Daniel Fetchinson wrote: > funcs = [ lambda x: x**i for i in range( 5 ) ] Here's another solution: from functools import partial funcs = [partial(lambda i, x: x**i, i) for i in range(5)] Notice that the arguments i and x are defined in the opposite order. T

Re: lambda in list comprehension acting funny

On 7/11/2012 11:53 PM, Steven D'Aprano wrote: On Wed, 11 Jul 2012 21:05:30 -0400, Dennis Lee Bieber wrote: {non sequitur: I still recall my archaic C++ class with the OOAD assignment of designing said calculator -- we never had to implement one, just design the basic classes/methods/attributes

Re: lambda in list comprehension acting funny

On Thursday, July 12, 2012 11:51:04 AM UTC+8, Steven D'Aprano wrote: > On Wed, 11 Jul 2012 20:39:45 -0700, 8 Dihedral wrote: > > > I'll contribute my way of python programming: > > > > def powerb(x, b): # > > return x**b > > Here's a shorter version: > > py> pow >

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 13:21:34 -0700 (PDT) John Ladasky wrote: > Exactly. It's threads like these which remind me why I never use lambda. I > would rather give a function an explicit name and adhere to the familiar > Python syntax, despite the two extra lines of code. I don't even like the > nam

Re: ANN: PollyReports 1.5 -- Band-oriented PDF Report Generator

On Thu, 12 Jul 2012 10:41:52 +1000 Simon Cropper wrote: > That said... with more than a passing interest in software and > content licensing I looked at how the work was licensed. A > none-standard license like this makes most people stop and think > "will this be a problem if I use this in my w

Re: lambda in list comprehension acting funny

On Wed, 11 Jul 2012 22:04:51 -0700, 8 Dihedral wrote: > I have to make sure my functor to keep the state variable values for > different objects that call the same functor to behave correctly in > order to avoid passing extra parameters in various objects using the > same functor. Yo dawg,

Re: Python and Qt4 Designer

On 12 jul, 02:59, Vincent Vande Vyvre wrote: > On 11/07/12 17:37, Jean Dubois wrote: > > > > > > > > > I'm trying to combine python-code made with QT4 designer with plain > > python statements like > > file = open("test","w") > > Can anyone tell me what I have to  add to the following code just to

Re: lambda in list comprehension acting funny

In article , Daniel Fetchinson wrote: > > funcs = [ lambda x: x**i for i in range( 5 ) ] > > print funcs[0]( 2 ) > > print funcs[1]( 2 ) > > print funcs[2]( 2 ) > > > > This gives me > > > > 16 > > 16 > > 16 > > > > When I was excepting > > > > 1 > > 2 > > 4 > > > > Does anyone know why? In Pyt