Question

我正在尝试根据年龄组对数组进行排序，然后是性别。我已经提出了一个解决方案，它可以工作，但我认为代码可以在某个地方改进，但我无法弄清楚如何。以下是示例输入：

// removed

我的代码：

// removed code

我得到的输出是正确的：

male 2,0,0,0,1,0,0,0,0
female 0,0,0,1,3,1,0,0,0

我很确定在速度性能方面有更好的方法来实现这一目标。有任何想法吗？

Answer 1

您可以使用array#reduce。

＆＃13;

var obj = [[{"age":41,"gender":"male"}],[{"age":10,"gender":"male"}],[{"age":10,"gender":"male"}],[{"age":31,"gender":"female"}],[{"age":58,"gender":"female"}],[{"age":50,"gender":"female"}],[{"age":50,"gender":"female"}],[{"age":50,"gender":"female"}]];

var result = obj.reduce(function(data,a){
  ++data[a[0]['gender']][a[0]['age'] > 80 ? data[a[0]['gender']].length : Math.ceil(a[0]['age'] / 10 - 1)];
  return data;
},{'male' : Array(9).fill(0), 'female' : Array(9).fill(0)});

console.log(result);

＆＃13;

如果要对对象进行排序，可以使用自定义排序功能

＆＃13;

var obj = [[{"age":41,"gender":"male"}],[{"age":10,"gender":"male"}],[{"age":10,"gender":"male"}],[{"age":31,"gender":"female"}],[{"age":58,"gender":"female"}],[{"age":50,"gender":"female"}],[{"age":50,"gender":"female"}],[{"age":50,"gender":"male"}],[{"age":50,"gender":"female"}]]

var result = obj.sort(function(a,b){
    return a[0].age - b[0].age || a[0].gender.localeCompare(b[0].gender);
});

console.log(result);

＆＃13;

Answer 2

您的代码需要4到6毫秒才能对您的样本数据执行。

function ageIndex(elem) {
    var age = elem[0].age;
    if (age <= 0) return 0;
    else if (age > 80) return 8;
    else return Math.floor((age - 1) / 10);
}

function gender(elem) { return elem[0].gender }

var ageGroup = ['0-10', '11-20', '21-30', '31-40', '41-50', '51-60', '61-70', '71-80', '80+'];

var maleData = new Array(ageGroup.length).fill(0);

var femaleData = new Array(ageGroup.length).fill(0);

l = arr.length;

for (var i = 0; i < l; i++) {
    if (gender(arr[i]) == "male") maleData[ageIndex(arr[i])]++;
    else femaleData[ageIndex(arr[i])]++;
}

console.log("male " + maleData)
console.log("female " + femaleData)

这个一直给我1毫秒。也许是因为我将数组长度存储在一个变量中，而不是每次都计算它。

Javascript按年龄组排序数组，后跟性别

2 个答案: