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Re: 3 word story 17 Years Ago by kAtHicKa comprehension. Even so, Re: comprehending list comprehension 14 Years Ago by snippsat … >>> #So how to do this with list comprehension? >>> l = [i+0 for i in… 8] >>> #If we write this without list comprehension >>> l = [] >>> for i…gt;[/CODE] [CODE] #The basic #list comprehension. l = [expr for-clause if-clause] #Without list comprehension. l = [] for variable in sequence :… Experimenting with List Comprehension (Python) 18 Years Ago by vegaseat A list comprehension derives a new list from an existing list, and was adopted by Python from the Haskell language. This snippet tries to explain the development of list comprehension and shows a number of uses, including nested list comprehension. The benefits are simplicity (after an initial learning bump) and in most cases speed improvements. Re: break a list comprehension 13 Years Ago by snippsat …prematurely to prevent unnecessary iterations[/QUOTE] Yes list comprehension are faster than ordinary loop,but dont do…;ZeroDivisionError has happend''' [/CODE] So write it without list comprehension. [CODE] try: l= [] for x in range(5… '''-->1.46803546261'''[/CODE] As ecpectet list comprehension is a litte faster than the ordinary loop,… Re: List Comprehension 18 Years Ago by vegaseat List comprehension is something Python borrowed from a language called Haskell. It … two functions and you can get an idea how list comprehension works within the one-line [...]. [code=pyhon]# using the module… list of even numbers from 0 to 99998 using list comprehension much faster in CPU time than the standard loop with… Re: Can list comprehension do this? 17 Years Ago by sneekula …i: dates.append(i) break print dates # ... or list comprehension ... dates2 = [i for i in files for j in …[/code][/quote]I sort of can see how list comprehension evolves from the individual for loops. Is there anything …list comprehension can do that one could not write out with… Re: Can list comprehension do this? 17 Years Ago by jrcagle [quote=sneekula;304172]Is there anything list comprehension can do that one could not write out with individual … in principle. However, in practice, list comprehension makes the code much more comprehensible. So: list comprehension does better code maintenance. :) Mathematically, [code… comprehending list comprehension 14 Years Ago by flatree … to Python and I am trying to understand how list comprehension works. I start with a list of nested lists (lis1…), make a copy using list comprehension to give lis2 (in the function scan()). I use a… Deconstructing List Comprehension 13 Years Ago by pixeldroid …"]found a thread here[/URL] which explains "list comprehension". The code I'm analyzing uses that, so I… shown how to convert it to a string using list comprehension: [code=python]jntStringList = ' '.join([j.name() for j in tmpJnts… Re: Deconstructing List Comprehension 13 Years Ago by griswolf … that one. And, by the way: This isn't list comprehension. Comprehension creates a list from some form of generator. [url]http… Re: Deconstructing List Comprehension 13 Years Ago by TrustyTony …;> [3*x for x in vec] [/CODE] as list comprehension so I think poster was right to call [CODE]jntStringList… = ' '.join([j.name() for j in tmpJnts])[/CODE] a list comprehension also. The speed question becomes even more interesting if you… Re: break a list comprehension 13 Years Ago by snippsat Exception handling in list comprehension is difficult/impossible. Here is Alex Martelli answer to the … impossible, literally speaking, to "handle exceptions in a list comprehension"[/QUOTE] [url]http://stackoverflow.com/questions/1528237/how-can… Re: break a list comprehension 13 Years Ago by snippsat That`s not exceptions handling in list comprehension,i think Alex Martelli answer is the correct answer to exception handling in list comprehension. [QUOTE]so it's impossible, literally speaking, to "handle exceptions in a list comprehension" [/QUOTE] Re: break a list comprehension 13 Years Ago by TrustyTony …snippsat;1264312]That`s not exceptions handling in list comprehension,i think Alex Martelli answer is the correct answer… to exception handling in list comprehension.[/QUOTE] But the point of this thread not …but [B]short circuit break from middle of list comprehension when solution is found.[/B] Exception is just mechanism… Nested List comprehension 13 Years Ago by prexioso Hi all!!! I have some problems with List comprehension in Python. How can I obtain these two nested list using comprehension? list1 = [[1,2,3],[4,5,6],[7,8,9]] list2 = [[1,0,0],[0,1,0],[0,0,1]] (identity matrix) where list1 and list2 are square matrix of 'n' size thank you in advance!!! Progress indicator from long running list comprehension 12 Years Ago by TrustyTony … end up to have very slow running code in list comprehension statement. Because you have not yet tested the code fully… statements for verification. But how to put print in list comprehension. If you are using function to produce the result you… Re: Haskell List Comprehension 11 Years Ago by sepp2k … duplicated. Regarding list comprehensions: In its simplest form a list comprehension has the form `[expressionInvolving item | item <- items]`.…list `items`. For example you can use a list comprehension to replace each occurence of the string "foo&…`map` can do the same thing as the list comprehension. Also in real code I would move the if-… Re: comprehending list comprehension 14 Years Ago by vegaseat You can not make a copy of a nested list that way, you have to use module copy ... lis2 = copy.deepcopy(lis1) rather then the list comprehension, since the nested list in [B]i[/B] is still passed as a reference. Re: Deconstructing List Comprehension 13 Years Ago by griswolf My fault for bad reference to "'this' (isn't list comprehension)". By 'this' I referred to the string join part, not the list creation in the initial code, but I did not make it clear. Re: break a list comprehension 13 Years Ago by TrustyTony … putting them in opposite order in the end of list comprehension. It is maybe possible to use generator expressions to imitate… stupid experiment of doing return function for linear search list comprehension: [CODE]def ret(a): raise StopIteration, str(a) target ='c… Re: break a list comprehension 13 Years Ago by TrustyTony [QUOTE=vegaseat;1263414]Replace your list comprehension with a generator expression ( simply replace [] with () ), then you can … that this code does not demonstrate the stopping of list comprehension or generator in first found answer, but goes through all… Re: break a list comprehension 13 Years Ago by snippsat [QUOTE]But the point of this thread not exception handling, but short circuit break from middle of list comprehension when solution is found. Exception is just mechanism that we must use if we do not use generator. [/QUOTE] Yes i know,and for me the correct anwer is to say that exception cannot be used inside a list comprehension. Re: List Comprehension to Create Multiple Buttons 11 Years Ago by Ene Uran … Tkinter's Radiobutton widget create muliple radio buttons with list comprehension ''' try: # Python2 import Tkinter as tk except ImportError: # Python3 import… List Comprehension 18 Years Ago by bumsfeld I hope the spelling isn't too far off, but what is list comprehension statement and why would one use it? Can list comprehension do this? 17 Years Ago by jrcagle … the items in months. Can this be done with list comprehension? Doesn't work: dates = [i for i in files if… Re: Can list comprehension do this? 17 Years Ago by vegaseat … in i: dates.append(i) break print dates # ... or list comprehension ... dates2 = [i for i in files for j in months… List comprehension without filter? 13 Years Ago by cyon … of values in a list of lists using a list comprehension without filtering the values that are not passed through the… break a list comprehension 13 Years Ago by ihatehippies … terminated prematurely to prevent unnecessary iterations. I know that list comprehension is fast that the 'for' statement, but I'm having… Re: break a list comprehension 13 Years Ago by vegaseat Replace your list comprehension with a generator expression ( simply replace [] with () ), then you can … Re: break a list comprehension 13 Years Ago by snippsat [QUOTE]This expression does not raise the zero division error, so it is not timing the same thing.[/QUOTE] Yes i know that,the timing was to shown speed off list comprehension vs ordinary loop.