Python : Async random broken?-CodePudding

so rn I am working in asynchronous python, and i have to deal with random number. Problem is that, for numbers between 0 and 4, I get the same numbers very often, like as follows :

3 2 0 2 4 0 1 4 2 1 4 2 1 3 2 3 2 2 2 1 0 3 2 2 2 0 0 4 3 0 3 4 4 0 3 3 3 3 2 4 4 4 0

of course there is only five possibilities but look at the end, i got 4 number 3 in a row, which is roughly 1/625 chance, and we don't talk about the times i get the same number 3 times in a row.

My code looks like this :

when async ready :
  random.seed(time.time())

async event:
  index = random.randint(0,4)
  async.send(someList[index])

Also it is a discord bot so the code runs continuously, so the seed is only donc once if that matters

CodePudding user response：

Without a more complete, yet minimal example, we cannot be sure if the code you use works as intended, but in a 42 element long list, it is quite common to have a value repeated 4 times in a row. Check the following code that generates 1000 times a 42 long random list, checks the longest repetition in each list, and counts how often happens it.

import random
import matplotlib.pyplot as plt


length_of_longest = []

for j in range(1000):
    random.seed(j)
    rndstr = "".join([str(random.randint(0, 4)) for _ in range(42)])
    for i in range(1, 42):
        total = 0
        for my_str in "01234":
            for_my_str = rndstr.count(my_str*i)
            total  = for_my_str
        if total == 0:
            length_of_longest.append(i-1)  # this length was not found
            break

# plot the results
fig, ax = plt.subplots()
ax.set_xticks([i 0.5 for i in range(8)], labels=range(8))
fig.patch.set_facecolor('white')
plt.hist(length_of_longest,bins=range(0,max(length_of_longest) 2))

This produces the following plot:

The x-axis tells how often was the longest repetition x long (e.g. at x=5, then there was a 11111 or 33333 or ... in the sequence), and y tells how many series were found with this property out of 1000.

It can be seen that in around 15%-20% of the cases, the length of the longest sequence is 4, but it can also occur a couple of times out of 1000, that the same value is chosen 7 times in a row.