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Creating 2D array without Numpy
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Creating 2D array without Numpy
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(Jan-27-2017, 09:43 AM)ichabod801 Wrote: The first way doesn't work because [[0] * n] creates a mutable list of zeros once. Then when the second *n copies the list, it copies references to first list, not the list itself. So you have a list of references, not a list of lists. The second way a new [0] * n is created each time through the loop. That way there is no copying being done, so you end up with an actual list of lists. I often do the second way with a list comprehension:
 [[0] * n for row in n] 

So there is no way to do this by one line code unless to use numpy?

L
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Messages In This Thread
Creating 2D array without Numpy - by landlord1984 - Jan-27-2017, 08:57 AM
RE: Creating 2D array without Numpy - by ichabod801 - Jan-27-2017, 09:43 AM
RE: Creating 2D array without Numpy - by landlord1984 - Jan-27-2017, 05:29 PM
RE: Creating 2D array without Numpy - by ichabod801 - Jan-28-2017, 01:34 AM

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