How to randomly select elements from an array in python?

Question

I need to randomly select elements from a list. Currently, I will sometimes select too many copies of an element from the original list eg:

Original List: [0, 1, 2, 3, 4]

3 Randomly Selected Elements: [4, 4, 4]

I do not want multiple 4s selected if there was only 1 in the original list.

What should I do to not take more copies of a value than exists in the first array?

You random.shuffle your list and pop elements from it till empty. Or use random.sample ... — Patrick Artner, Jan 27 '20 at 19:33
Does this answer your question? [How do I create a list of random numbers without duplicates?](https://stackoverflow.com/questions/9755538/how-do-i-create-a-list-of-random-numbers-without-duplicates) — Patrick Artner, Jan 27 '20 at 19:35
https://docs.python.org/3.8/library/random.html#random.sample -you even Tagged it sample... — Patrick Artner, Jan 27 '20 at 19:36
https://docs.python.org/3.8/library/random.html#random.shuffle ` — Patrick Artner, Jan 27 '20 at 19:37

score -1 · Accepted Answer · answered Jan 27 '20 at 19:44

-1

A solution is to remove the elements from the original list when you select them.

import random 
original_list = [1, 2, 2, 3, 3, 3]
number_of_random_selections = 4
random_selections = []

for i in range(0, len(original_list)):
    random_index = random.randint(0, number_of_random_selections)
    random_selection = original_list[random_index]
    random_selections.append(random_selection)
    original_list.remove(random_selection)

print(random_selections)

answered Jan 27 '20 at 19:44

Branson Smith

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You already imported `random` but not use functions from it. Also modifying original list is not the best idea. – Olvin Roght Jan 27 '20 at 19:50
I agree that the original list should not be changed, but was hoping to provide a solution that was focused on answering the asker's specific question, and leave those decisions to him. Also, I imported random for the randint() function. It sounds like you could help both me and OP by providing an improved answer :) – Branson Smith Jan 27 '20 at 19:58
[`random.sample(original_list, number_of_random_selections)`](https://docs.python.org/3/library/random.html#random.sample) – Olvin Roght Jan 27 '20 at 20:02

How to randomly select elements from an array in python?

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