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Creating 2D array without Numpy
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Creating 2D array without Numpy
#1
I want to create a 2D array and assign one particular element.
The second way below works.
But the first way doesn't.
I am curious to know why the first way does not work.
Is there any way to create a zero 2D array without numpy and without loop?



The first way is:

n=10
Grid=[[0]*n]*n 
Grid[1][1]=1
Quote:[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]

The second way is:
n=10
Grid = [0] * n
for i in range(n):
    Grid[i] = [0] * n
Grid[1][1]=1
Quote:[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
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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 ichabod801 - Jan-28-2017, 01:34 AM

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