Das deutsche Python-Forum

Code: Alles auswählen

prob_var = {v53:123, v07:34, v19:8976, v66:670, ...}  #prob = prob_var[var]

Code: Alles auswählen

prob_var = {v53:123, v07:34, v19:8976, v66:670}
distribution = sorted([(v,k) for k,v in prob_var.iteritems()], reverse=True) # reverse since more probable is more probable ;)
num = random.randint(1, sum(prob_var.values()))
for value, var in distribution:
    if value < num:
        break
# var ist deine Zielvariable

Code: Alles auswählen

#!/usr/bin/env python
from bisect import bisect
from random import random


def weighted_choice(items2weights):
    cumulated_weights = list()
    running_total = 0
    for weight in items2weights.viewvalues():
        running_total += weight
        cumulated_weights.append(running_total)
    return items2weights.keys()[
        bisect(cumulated_weights, random() * cumulated_weights[-1])
    ]

Code: Alles auswählen

d = {1: 5, 2: 3, 3: 7, 4: 20, 5: 2}
urn = []
for k, v in d.iteritems():
    urn.extend([k] * v)
...
def pick(urn):
    return urn[int(random.random() * len(urn))]