在数组中，将每个元素与每个元素进行比较并显示差异

Question

我想制作一个 javascript 算法，将 flight1 的值与 rest 的两个值进行比较，然后将航班 2 与航班 1 和航班 3 进行比较。

结果应该是 dif_flight1_flight2 = 10, dif_flight1_flight3 = 110。

var x = [
      ['flight1', '190'],
      ['flight2', '200'],
      ['flight3', '300']
]

Answer 1

存储您的变量，然后根据这些值计算差异。 Google 如何在 JS 中访问/遍历 2d arrays。

var flight1 = (x[0][1]); // 190

var flight2 = (x[1][1]); // 200

var flight3 = (x[2][1]); //300

// Note the variables can be named anything that I declared
var difference = flight2 - flight1; //difference equals 10

Answer 2

你可以这样做：

 var x = [
      ['flight1', '190'],
      ['flight2', '200'],
      ['flight3', '300']
];

var result = [];
for(let i = 1; i < x.length; i++) {
    let value = parseInt(x[0][1]) - parseInt(x[i][1]);
    let element = 'diff_' + x[0][0] + '_' + x[i][0];
    result.push({
        key: element,
        value: Math.abs(value)
    });
}

该算法取第一个元素，并将其与其他 N -1 个元素进行比较。 在结果数组上，您有所有差异。

一个问题：你为什么使用数组数组而不是 Object 数组？

Answer 3

每个值都必须与每个值进行比较...

function test_dif(){

        var x = [
              ['flight1', '190'],
              ['flight2', '200'],
              ['flight3', '300']
        ];

        var result = [];
        for(let i = 0; i < x.length; i++) {
            for(let c = 0; c < x.length; c++){
                    let value = parseInt(x[c][1]) - parseInt(x[i][1]);
                    let element = 'diff_' + x[c][0] + '_' + x[i][0];
                    result.push({
                        key: element,
                        value: Math.abs(value)
                    });
           }
         }

        return result;

    }

结果：

0: {key: "diff_flight1_flight1", value: 0}
1: {key: "diff_flight2_flight1", value: 10}
2: {key: "diff_flight3_flight1", value: 110}
3: {key: "diff_flight1_flight2", value: 10}
4: {key: "diff_flight2_flight2", value: 0}
5: {key: "diff_flight3_flight2", value: 100}
6: {key: "diff_flight1_flight3", value: 110}
7: {key: "diff_flight2_flight3", value: 100}
8: {key: "diff_flight3_flight3", value: 0}