Liz Sander Liz Sander - 6 months ago 13
Python Question

Binary numpy array to list of integers?

I have a binary array, and I would like to convert it into a list of integers, where each int is a row of the array.

For example:

from numpy import *
a = array([[1, 1, 0, 0], [0, 1, 0, 0], [0, 1, 1, 1], [1, 1, 1, 1]])


I would like to convert
a
to
[12, 4, 7, 15]
.

Answer

I once asked a similar question here. Here was my answer, adapted for your question:

def bool2int(x):
    y = 0
    for i,j in enumerate(x):
        y += j<<i
    return y

In [20]: a
Out[20]: 
array([[1, 1, 0, 0],
       [0, 1, 0, 0],
       [0, 1, 1, 1],
       [1, 1, 1, 1]])

In [21]: [bool2int(x[::-1]) for x in a]
Out[21]: [12, 4, 7, 15]
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