random - 在 python 3.5 中使用 random.choices() 的替代方法是什么

Question

既然 random.choices() 在 python 3.5 中不可用，那么这个函数是否有任何替代方法？

Answer 1

按照 Mark Dickinson 的建议将代码从 python 3.6 复制到

from itertools import accumulate as _accumulate, repeat as _repeat
from bisect import bisect as _bisect
import random
def choices(population, weights=None, *, cum_weights=None, k=1):
    """Return a k sized list of population elements chosen with replacement.
    If the relative weights or cumulative weights are not specified,
    the selections are made with equal probability.
    """
    n = len(population)
    if cum_weights is None:
        if weights is None:
            _int = int
            n += 0.0    # convert to float for a small speed improvement
            return [population[_int(random.random() * n)] for i in _repeat(None, k)]
        cum_weights = list(_accumulate(weights))
    elif weights is not None:
        raise TypeError('Cannot specify both weights and cumulative weights')
    if len(cum_weights) != n:
        raise ValueError('The number of weights does not match the population')
    bisect = _bisect
    total = cum_weights[-1] + 0.0   # convert to float
    hi = n - 1
    return [population[bisect(cum_weights, random.random() * total, 0, hi)]
            for i in _repeat(None, k)]

现在您可以安心地使用choices 功能了!