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Python - multiline array

in C ++ I can write:

int someArray[8][8];
for (int i=0; i < 7; i++)
   for (int j=0; j < 7; j++)
      someArray[i][j] = 0;

And how can I initialize multi-line arrays in python? I tried:

array = [[],[]]
for i in xrange(8):
   for j in xrange(8):
        array[i][j] = 0
+5
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5 answers
>>> [[0]*8 for x in xrange(8)]
[[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]]
>>>
+7
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You asked about initializing a list of lists. This is a very useful data structure, but it has an important difference from a 2D array in C ++: there is no guarantee that all lines are the same length (i.e. What len(a[0])==len(a[1])(while in C ++ you have this guarantee).

So, another solution that may be convenient uses a NumPy array datatype, for example:

import numpy as np
array = np.zeros((8,8))
+7
source

:

array = []
for i in xrange(8):
    array.append( [0] * 8 )
+3
array = [[0]*8 for i in xrange(8)]
+3
[[0]*8 for x in range(8)]
+2

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