Shuffling a list of objects

Question

I have a list of objects and I want to shuffle them. I thought I could use the random.shuffle method, but this seems to fail when the list is of objects. Is the

Answer 1

One can define a function called shuffled (in the same sense of sort vs sorted)

def shuffled(x):
    import random
    y = x[:]
    random.shuffle(y)
    return y

x = shuffled([1, 2, 3, 4])
print x

Answer 2

If you happen to be using numpy already (very popular for scientific and financial applications) you can save yourself an import.

import numpy as np    
np.random.shuffle(b)
print(b)

https://numpy.org/doc/stable/reference/random/generated/numpy.random.shuffle.html

Answer 3

you could build a function that takes a list as a parameter and returns a shuffled version of the list:

from random import *

def listshuffler(inputlist):
    for i in range(len(inputlist)):
        swap = randint(0,len(inputlist)-1)
        temp = inputlist[swap]
        inputlist[swap] = inputlist[i]
        inputlist[i] = temp
    return inputlist

Answer 4

you can either use shuffle or sample . both of which come from random module.

import random
def shuffle(arr1):
    n=len(arr1)
    b=random.sample(arr1,n)
    return b

OR

import random
def shuffle(arr1):
    random.shuffle(arr1)
    return arr1

Answer 5

random.shuffle should work. Here's an example, where the objects are lists:

from random import shuffle
x = [[i] for i in range(10)]
shuffle(x)

# print(x)  gives  [[9], [2], [7], [0], [4], [5], [3], [1], [8], [6]]
# of course your results will vary

Note that shuffle works in place, and returns None.

Answer 6

""" to shuffle random, set random= True """

def shuffle(x,random=False):
     shuffled = []
     ma = x
     if random == True:
         rando = [ma[i] for i in np.random.randint(0,len(ma),len(ma))]
         return rando
     if random == False:
          for i in range(len(ma)):
          ave = len(ma)//3
          if i < ave:
             shuffled.append(ma[i+ave])
          else:
             shuffled.append(ma[i-ave])    
     return shuffled