javascript - 使用javascript查找最接近的数组索引

Question

我有以下功能:

(function(){
    function closest (num, arr) {
        var curr = arr[0];
        var diff = Math.abs (num - curr);
        for (var val = 0; val < arr.length; val++) {
            var newdiff = Math.abs (num - arr[val]);
            if (newdiff < diff) {
                diff = newdiff;
                curr = arr[val];
            }
        }
        return curr;
    }
    var _array = [2, 42, 82, 122, 162, 202, 242, 282, 322, 362],
        _number = 155;

    return closest (_number, _array);
})()

结果是 162

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在这个数组中，我想显示最接近结果的索引!结果应该是数字 4

Answer 1

您可以存储索引并返回该值。

function closest(num, arr) {
    var curr = arr[0],
        diff = Math.abs(num - curr),
        index = 0;

    for (var val = 0; val < arr.length; val++) {
        let newdiff = Math.abs(num - arr[val]);
        if (newdiff < diff) {
            diff = newdiff;
            curr = arr[val];
            index = val;
        }
    }
    return index;
}

var array = [2, 42, 82, 122, 162, 202, 242, 282, 322, 362],
    number = 155;

console.log(closest(number, array));