bps roulette wheel !

roulette.py

__author__ = 'jayvyas'
import random
import math

def roulette_wheel(model):
    wheel = [None] * len(model)
    cumProb = 0.0
    for i in range(len(model)):
        (item, prob) = model[i]
        print(i,item,prob)
        cumProb += prob
        wheel[i] = (item, cumProb)
    return wheel


## Corresponds to the following roulette wheel...
## [.1,.8, .9, .95, 1.0]
wheel = roulette_wheel(
    [
        ("fish food",0.1),
        ("dog food",0.7),
        ("bird food",0.1),
        ("small rodent food",0.05),
        ("reptile food",0.05)
    ])

for i in range(1000):
    r = random.random()
    print([it for (it, cp) in wheel if cp >= r ][0])

dog food
fish food
dog food
dog food
dog food
fish food
dog food
dog food
bird food
dog food
fish food
dog food
dog food
dog food
dog food
small rodent food
dog food
dog food