looking for a random matrix of zeros and ones in python with a limited amount of ones

Question

I am generating a matrix of zeros and ones in python as

poblacionCandidata = np.random.randint(0, 2, size=(4, 2))

However, I need for it to be only two ones at most in each row.

I have checked this question, but it is too complex for me.

Can anyone help me with this

The result should be something like

[[1 1 0 0]
 [1 0 0 1]
 [1 0 0 0]
 [0 1 0 0]]

Best regards

Answer 1

You could just use a loop:

import numpy as np

def generate_matrix(rows: int, cols: int, max_ones_per_row: int) -> np.ndarray:
    """
    Generate a matrix with up to a specified number of ones per row.
    
    :param rows: The number of rows in the matrix.
    :param cols: The number of columns in the matrix.
    :param max_ones_per_row: The maximum number of ones to be placed in each row.
    :return: A numpy array representing the generated matrix.
    """
    matrix = np.zeros((rows, cols), dtype=int)
    for i in range(rows):
        ones_per_row = np.random.randint(0, max_ones_per_row + 1)
        ones_indices = np.random.choice(cols, ones_per_row, replace=False)
        matrix[i, ones_indices] = 1
    return matrix

poblacionCandidata = generate_matrix(rows=4, cols=4, max_ones_per_row=2)
print(poblacionCandidata)

Example Output:

[[1 0 0 0]
 [0 0 1 1]
 [0 0 0 0]
 [0 1 0 0]]