Re: Best way to have a for-loop index?
Sometimes C++ is the right tool/style for the job, but I don't need the speed or efficiency of C++. -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
Roy Smith wrote: In article [EMAIL PROTECTED], [EMAIL PROTECTED] wrote: I write a lot of code that looks like this: for myElement, elementIndex in zip( elementList, range(len(elementList))): print myElement , myElement, at index: ,elementIndex My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? TIA, Andrew The real question is *why* do you want the index? If you're trying to iterate through list indicies, you're probably trying to write C, C++, Fortran, Java, etc in Python. Interesting. I just wrote some tools today that parse through a bunch of logfiles and print out something like: unmatched memory allocation in line XXX, or something like that. All of them have a main loop like this: for lineNumber, line in enumerate(file(some.log)): ... I don't think there's anything wrong with that, is there a better way to do it? Personally, I don't think enumerate would be there if it always encouraged an unpythonic programming style. But then again, I'm not dutch, so I couldn't tell... ;-) -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
roy spewed: The real question is *why* do you want the index? If you're trying to iterate through list indicies, you're probably trying to write C, C++, Fortran, Java, etc in Python. Could we stop the stupid continual beratement of people validly asking about enumerate()? Yes, we want to discourage: for i in xrange(len(seq)): seq[i] but in this case, and many other cases, that is clearly not the question being posed. enumerate is one of the most useful built-ins and a love the way it reads in code. Stop the index-hate. -Mike -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
On 9 Mar 2006 16:32:24 -0800 [EMAIL PROTECTED] wrote: I write a lot of code that looks like this: for myElement, elementIndex in zip( elementList, range(len(elementList))): print myElement , myElement, at index: ,elementIndex My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? In fact it is so common a need, there is a built-in function called enumerate that does the 'zip' for you: for elementIndex, myElement in enumerate(elementList): print myElement , myElement, at index: ,elementIndex -- Terry Hancock ([EMAIL PROTECTED]) Anansi Spaceworks http://www.AnansiSpaceworks.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
On Thu, 09 Mar 2006 20:22:34 -0500, Roy Smith wrote: My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? TIA, Andrew The real question is *why* do you want the index? If you're trying to iterate through list indicies, you're probably trying to write C, C++, Fortran, Java, etc in Python. That's a bit harsh, surely? Well-meaning, but still harsh, and untrue. Wanting to walk through a list replacing or modifying some or all items in place is not unpythonic. Sure, you could simply create a new list: L = [1, 2, 3, 4] newL = [] for item in L: if item % 3 == 0: newL.append(item) else: newL.append(item**2) but that's wasteful if the list is big, or if the items are expensive to copy. Isn't this more elegant, and Pythonic? L = [1, 2, 3, 4] for index, item in enumerate(L): if item % 3 != 0: L[index] = item**2 -- Steven. -- http://mail.python.org/mailman/listinfo/python-list
Best way to have a for-loop index?
I write a lot of code that looks like this: for myElement, elementIndex in zip( elementList, range(len(elementList))): print myElement , myElement, at index: ,elementIndex My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? TIA, Andrew -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
[EMAIL PROTECTED] wrote: I write a lot of code that looks like this: for myElement, elementIndex in zip( elementList, range(len(elementList))): print myElement , myElement, at index: ,elementIndex My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? TIA, Andrew enumerate(iterable) Return an enumerate object. iterable must be a sequence, an iterator, or some other object which supports iteration. The next() method of the iterator returned by enumerate() returns a tuple containing a count (from zero) and the corresponding value obtained from iterating over iterable. enumerate() is useful for obtaining an indexed series: (0, seq[0]), (1, seq[1]), (2, seq[2]), New in version 2.3 Michael -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
[EMAIL PROTECTED] wrote: I write a lot of code that looks like this: for myElement, elementIndex in zip( elementList, range(len(elementList))): print myElement , myElement, at index: ,elementIndex My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? for elementIndex, myElement in enumerate(elementList): print myElement , myElement, at index: ,elementIndex --Scott David Daniels [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
Re: Best way to have a for-loop index?
In article [EMAIL PROTECTED], [EMAIL PROTECTED] wrote: I write a lot of code that looks like this: for myElement, elementIndex in zip( elementList, range(len(elementList))): print myElement , myElement, at index: ,elementIndex My question is, is there a better, cleaner, or easier way to get at the element in a list AND the index of a loop than this? TIA, Andrew The real question is *why* do you want the index? If you're trying to iterate through list indicies, you're probably trying to write C, C++, Fortran, Java, etc in Python. Can you describe exactly what it is that you're trying to do? -- http://mail.python.org/mailman/listinfo/python-list
