数组内值的 JavaScript 平均值

Question

JSON:

[{"id":"1","user":"001","answer":"1,1,3,2,2,1,3,2"},
{"id":"2","user":"002","answer":"2,3,3,2,1,1,3,2"},
{"id":"3","user":"003","answer":"3,5,3,5,3,1,3,2"}]

JavaScript:

jQuery.ajax({
    url: "file.json",
    type: "POST",
    dataType: "json",
    async: false,
    success: function (data) {
    var arr = [];
    for (i = 0; i < data.length; i++) { 
        arr.push(data[i].answer);
    }
    console.log(arr);
});

我想做的是对 3 个 answer 的每个值取平均值，以防万一，这将给出这 8 个平均值:

2,3,3,3,2,1,3,2

Answer 1

const arrAvg = arr => arr.reduce((a,b) => a + b, 0) / arr.length;
console.log(arrAvg([1,2,3,4,5]));