Truncated random variable with given expected value

truncated_random.py

from random import random


def truncated_given_exp(minimum, maximum, expected):
  if expected == minimum: return expected
  maximum -= minimum
  expected -= minimum
  k = maximum/expected - 1 # Questa si comporta peggio della prima se expected - min < max - expected
  return minimum + maximum * random()**k


def test_sample(minimum, maximum, expected, tries=10**5):
  from statistics import mean
  sample = [truncated_given_exp(minimum, maximum, expected) for i in range(tries)]
  return min(sample), max(sample), mean(sample)


def test():
  for i in range(100):
    minimum = random() * 100
    maximum = random() * 1000 + minimum
    expected = random() * (maximum - minimum) + minimum
    print(f"Testing {minimum},\t{maximum},\t{expected}:")
    print( "Result: {},\t{},\t{}".format(*test_sample(minimum, maximum, expected)))