Python scipy百分位数的加权版本

我想把重量传给你。例如：

from scipy import stats
a = [1, 2, 3, 4]
val = 3
stats.percentileofscore(a, val)

weights = [2, 2, 3, 3]
weightedpercentileofscore(a, val, weights)

返回75，因为

a

中75%的值位于

val

3或以下

我想添加权重，例如：

from scipy import stats
a = [1, 2, 3, 4]
val = 3
stats.percentileofscore(a, val)

weights = [2, 2, 3, 3]
weightedpercentileofscore(a, val, weights)

应该返回70，因为（2+2+3）/（2+2+3+3）=7/10的权重落在3或以下

这也适用于十进制权重和大权重，因此仅扩展数组并不理想

---

是相关的，但计算百分位（例如，要求第10个百分位值），而不是某个值的特定百分位。

这应该可以完成这项工作

import numpy as np

def weighted_percentile_of_score(a, weights, score, kind='weak'):
    npa = np.array(a)
    npw = np.array(weights)

    if kind == 'rank':  # Equivalent to 'weak' since we have weights.
        kind = 'weak'

    if kind in ['strict', 'mean']:
        indx = npa < score
        strict = 100 * sum(npw[indx]) / sum(weights)
    if kind == 'strict':
        return strict

    if kind in ['weak', 'mean']:    
        indx = npa <= score
        weak = 100 * sum(npw[indx]) / sum(weights)
    if kind == 'weak':
        return weak

    if kind == 'mean':
        return (strict + weak) / 2


a = [1, 2, 3, 4]
weights = [2, 2, 3, 3]
print(weighted_percentile_of_score(a, weights, 3))  # 70.0 as desired.