Weighted randomness

[nier]

Hey

I am trying to figure out a very simple code to do some weighted randomness.

I have two values, and I have to randomly pick among them on each iteration.
But I need, let's say, the first value to be picked on 60% of the cases, and the second value to be picked on 40% of the cases.

Anyone can write me some code or even pseudo code to do that?

I know it is simple, I learned it one day in my life, but right now I'm blank!

Thank u a lot
Daniel

[bartonc]

Hey

I am trying to figure out a very simple code to do some weighted randomness.

I have two values, and I have to randomly pick among them on each iteration.
But I need, let's say, the first value to be picked on 60% of the cases, and the second value to be picked on 40% of the cases.

Anyone can write me some code or even pseudo code to do that?

I know it is simple, I learned it one day in my life, but right now I'm blank!

Thank u a lot
Daniel

I'm more of a mechanic than a mathematician (gui & device interfaces), but there sure are a lot of interesting looking functions with names like paretovariate in the random module. One of them has just gotta do what you're look for.

[dmr]

Here's an ugly way to do it: create a list of ten with 6 of one value and 4 of another, than randomly access the list.

import random
import math
 
s = [6,6,6,6,6,6,4,4,4,4]
 
for i in range(1,100):
  print s[ int( math.floor( random.random() * 10) ) ]
 

[ilikepython]

Here's an ugly way to do it: create a list of ten with 6 of one value and 4 of another, than randomly access the list.

import random
import math
 
s = [6,6,6,6,6,6,4,4,4,4]
 
for i in range(1,100):
  print s[ int( math.floor( random.random() * 10) ) ]
 

Just a little note: you don't need all that math to get a value from 1 to ten. Just do this:

print s[random.randint(0, 9)]
 

No biggie :)

[dmr]

Thanks, I don't know how I missed that. I've just started playing with Python and will remember it.