How to select random rows from a matrix in python scratch without any numpy library

Question

Hi i am trying to inplememt Genetic algorithm rollete wheel selection mechanism. I have done fitness and also the corresponding fitness probability. I need a code to randomly select rows from initial generated matrix.but only using scratch python bc i am not using any libary such as numpy or jupyter

Same like this one but without numpy

Select two random rows from numpy array

Thank you

Please include code snippets of what you are trying to accomplish. — mdf, Dec 15 '21 at 15:30
Same like this one but without numpy https://stackoverflow.com/questions/22835914/select-two-random-rows-from-numpy-array — Priya BB, Dec 15 '21 at 15:52
https://stackoverflow.com/questions/22835914/select-two-random-rows-from-numpy-array — Priya BB, Dec 15 '21 at 15:53
Please provide enough code so others can better understand or reproduce the problem. — Community, Dec 22 '21 at 09:55

mdf · Answer 1 · 2021-12-16T15:30:15.107

0

Use random.sample():

import random  # for random.sample

# This is an example matrix
A = [[1, 2, 3],
     [4, 5, 6],
     [7, 8, 9]]


num_random_rows_desired = 2
a = random.sample(A, num_random_rows_desired)
print(a)

edited Dec 16 '21 at 15:30

answered Dec 15 '21 at 19:58

mdf

133
8

it gives just one row in output randomly every time I want the row same as in this array A = [[1, 2, 3], [4, 5, 6], [7, 8, 9]] and also the rows which have smaller in some will be omitted like 1+2+3 = 6 it will be omitted 3 new rows will be generated randomly from remaining two rows of array A – Priya BB Dec 16 '21 at 13:12
Updated answer. – mdf Dec 16 '21 at 15:31

How to select random rows from a matrix in python scratch without any numpy library

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