How do I use Python to generate a random number that is greater than a specified one?

Question

By this I mean I need Python to generate any random number under one condition, it must be greater than the user defined number (lets say "x"), in other words it would be like saying x>num>infinity.

I tried using the random module but can't seem to figure anything out, as I tried something like this

import random
import math
inf=math.inf
x=15
random.randint(x,inf)

But that doesn't work because infinity is registered as a floating point number and the randint function only works with integers. I also tried something like this

import random
import math
inf=math.inf
x=15
random.uniform(x,inf)

This should work because the uniform function works with floating points, but it just ends up returning infinity every time.

This would mean that I need someway to get this done without using infinity (or math.inf) within my range, I just need the range to have a minimum (x) and no maximum at all. Any suggestions?

I'm running Python 3.6.0b4 on OS X Yosemite

Do you actually want an integer? Then `random.randint(x, sys.maxsize)` would do it, see https://stackoverflow.com/q/7604966/3001761 — jonrsharpe, Jul 01 '17 at 12:35
If you're okay with longs then you can make the number as big as your memory can fit. — cs95, Jul 01 '17 at 12:38
An uniform distribution can only be defined on a bounded interval. So, trying to use it between some value and infinity makes no sense. — Thierry Lathuille, Jul 01 '17 at 12:52
Voting to close as unclear because the requirement does not make **mathematical** sense, per @ThierryLathuille 's comment. — Karl Knechtel, Mar 08 '23 at 16:04

TomServo · Accepted Answer · 2017-07-01T13:21:48.023

2

There is no specific maximum integer. See this article

Use sys.maxsize instead.

sys.maxsize An integer giving the maximum value a variable of type Py_ssize_t can take. It’s usually 2^31 - 1 on a 32-bit platform and 2^63 - 1 on a 64-bit platform.

To limit the upper bound to some lesser value, one could simply define a maximum that is less than that implied by sys.maxsize. For example, the 64-bit maximum signed integer 9,223,372,036,854,775,807 could be limited to 999,999,999,999,999L for 15 decimal places. You could just use that or any long integer less than that implied by sys.maxsize.

edited Jul 01 '17 at 13:21

answered Jul 01 '17 at 12:37

TomServo

7,248
5
30
47

Is there any way to limit the output to a certain amount of digits? – Jad Jul 01 '17 at 13:07
@JadMoussa yes, of course see my edited answer above. Thanks for accepting! – TomServo Jul 01 '17 at 13:22

How do I use Python to generate a random number that is greater than a specified one?

1 Answers1