Generate a random number from an interval in Python

Question

How to generate a random number in the interval [-0.5, 0.5] using Python random() or randrange() functions?

Answer 1

If you want to stick with random() and use a varying bound, you could easily do:

from random import random
upper_limit = 0.5
lower_limit = -0.5
random() * (upper_limit - lower_limit) + lower_limit

This will always give you a random float between -0.5 and 0.5.

Answer 2

random returns a float and takes no arguments, randrange takes an upper and lower bound but takes and returns an int.

from random import randrange

print(randrange(-5, 5))

If you want floats use uniform:

from random import  uniform

uniform(-.5, .5)

Answer 3

this will do the trick random.random() - .5