常用统计类函数的python实现

"""
作者：皮蛋编程(https://www.pidancode.com)
创建日期：2022/3/18
修改日期：2022/3/18
功能描述：针对数字数组的常用统计函数Python实现
"""

import sys


class Stats:
    def __init__(self, sequence):
        # 将列表内的所有元素转换成浮点数
        self.sequence = [float(item) for item in sequence]

    def sum(self):
        if len(self.sequence) < 1:
            return None
        else:
            return sum(self.sequence)

    def count(self):
        return len(self.sequence)

    def min(self):
        if len(self.sequence) < 1:
            return None
        else:
            return min(self.sequence)

    def max(self):
        if len(self.sequence) < 1:
            return None
        else:
            return max(self.sequence)

    def avg(self):
        if len(self.sequence) < 1:
            return None
        else:
            return sum(self.sequence) / len(self.sequence)

    def median(self):
        if len(self.sequence) < 1:
            return None
        else:
            self.sequence.sort()
            return self.sequence[len(self.sequence) // 2]

    def stdev(self):
        if len(self.sequence) < 1:
            return None
        else:
            avg = self.avg()
            sdsq = sum([(i - avg) ** 2 for i in self.sequence])
            stdev = (sdsq / (len(self.sequence) - 1)) ** .5
            return stdev

    def percentile(self, percentile):
        if len(self.sequence) < 1:
            value = None
        elif (percentile >= 100):
            sys.stderr.write('ERROR: 百分比必须 < 100.  您提供的是: %s\n' % percentile)
            value = None
        else:
            element_idx = int(len(self.sequence) * (percentile / 100.0))
            self.sequence.sort()
            value = self.sequence[element_idx]
        return value


# 演示代码
sequence = [1.2, 2.6, 9, 13.8, 8.0]
stats = Stats(sequence)
print('求和：{}'.format(stats.sum()))
print('数组长度：{}'.format(stats.count()))
print('最大值：{}'.format(stats.max()))
print('最小值：{}'.format(stats.min()))
print('中位数：{}'.format(stats.median()))
print('标准差：{}'.format(stats.stdev()))
print('平均数：{}'.format(stats.avg()))
print('百分数：{}'.format(stats.percentile(70)))