[SOLVED] Generate random binary matrix with all theirs rows different using numpy

Issue

I need to generate a random binary matrix with dimensions m x n where all their rows are different among themselves. Using numpy I tried

import numpy as np
import random
n = 512
m = 1000

a = random.sample(range(0, 2**n), m)
a = np.array(a)
a = np.reshape(a, (m, 1))
np.unpackbits(a.view(np.uint8), axis=1)

But it is not suitable for my case because n > 128 and m > 1000. So, the code above generates only rows with at most 62 elements. Could you help me, please?

Solution

You could generate a random array of 0’s and 1’s with numpy.random.choice and then make sure that the rows are different through numpy.unique:

import numpy as np

m = 1000
n = 512

while True:
    a = np.random.choice([0, 1], size=(m, n))
    if len(np.unique(a, axis=0)) == m:
        break

Answered By – Tonechas

Answer Checked By – Willingham (BugsFixing Volunteer)