js 算数组平均值、最大值、最小值、偏差、标准差、中位数、数组从小打大排序、上四分位数、下四分位数

要算的数组命名为data

var sum = function(x,y){ return x+y;};　　//求和函数
var square = function(x){ return x*x;};　　//数组中每个元素求它的平方

var data = [1,1,3,5,5];　　//
var mean = data.reduce(sum)/data.length;
var deviations = data.map(function(x){return x-mean;});
var stddev = Math.sqrt(deviations.map(square).reduce(sum)/(data.length-1));

var max = Math.max.apply(null,data)
var min = Math.min.apply(null,data)

var compare = function (x, y) {//比较函数    if (x < y) {        return -1;    } else if (x > y) {        return 1;    } else {        return 0;    }};var mid; //中位数data.sort(compare); //数组排序if (data.length%2==0){    mid = (data[data.length/2]+data[data.length/2+1])/2}if (data.length%2!=0){    mid = data[(data.length+1)/2]}

console.log("平均值："+mean);console.log("偏差："+deviations);console.log("标准差："+stddev); console.log("最大值："+max); console.log("最小值："+min);console.log("中位数:"+mid);console.log("上四分位数:"+data[data.length/4]);console.log("下四分位数:"+data[data.length/4*3]);

原文地址：https://www.cnblogs.com/zheng123/p/9270231.html