Question

我正在尝试从2d javascript数组计算加权平均值。这是数组：

 var timestamp = [
  [1524751200, 6000],
  [1556287200, 6000],
  [1587909600, 6000],
  [1619445600, 6000],
  [1650981600, 3000],
  [1682517600, 3000],
  [1714140000, 3000],
  [1745676000, 3000],
  [1777212000, 1500],
  [1808748000, 1500],
  [1840370400, 1500],
  [1871906400, 1500],
  [1903442400, 750],
  [1934978400, 750],
  [1966600800, 750],
  [1998136800, 750],
  [2029672800, 375],
  [2061208800, 375],
  [2092831200, 375],
  [2124367200, 375],
  [2155903200, 187.5],
  [2187439200, 187.5],
  [2219061600, 187.5],
  [2250597600, 187.5],
  [2282133600, 93.75],
  [2313669600, 93.75],
  [2345292000, 93.75],
  [2376828000, 93.75],
  [2408364000, 46.875],
  [2439900000, 46.875],
  [2471522400, 46.875],
  [2503058400, 46.875],
  [2534594400, 23.4375],
  [2566130400, 23.4375],
  [2597752800, 23.4375],
  [2629288800, 23.4375],
  [2660824800, 11.71875],
  [2692360800, 11.71875],
  [2723983200, 11.71875],
  [2755519200, 11.71875],
  [2787055200, 5.859375],
  [2818591200, 5.859375],
  [2850213600, 5.859375],
  [2881749600, 5.859375],
  [2913285600, 2.9296875],
  [2944821600, 2.9296875],
  [2976444000, 2.9296875],
  [3007980000, 2.9296875],
  [3039516000, 1.46484375],
  [3071052000, 1.46484375],
  [3102674400, 1.46484375],
  [3134210400, 1.46484375],
  [3165746400, 0.732421875],
  [3197282400, 0.732421875],
  [3228904800, 0.732421875],
  [3260440800, 0.732421875],
  [3291976800, 0.3662109375],
  [3323512800, 0.3662109375],
  [3355135200, 0.3662109375],
  [3386671200, 0.3662109375],
  [3418207200, 0.18310546875],
  [3449743200, 0.18310546875],
  [3481365600, 0.18310546875],
  [3512901600, 0.18310546875],
  [3544437600, 0.091552734375],
  [3575973600, 0.091552734375],
  [3607596000, 0.091552734375],
  [3639132000, 0.091552734375],
  [3670668000, 0.0457763671875],
  [3702204000, 0.0457763671875],
  [3733826400, 0.0457763671875],
  [3765362400, 0.0457763671875],
  [3796898400, 0.02288818359375],
  [3828434400, 0.02288818359375],
  [3860056800, 0.02288818359375],
  [3891592800, 0.02288818359375],
  [3923128800, 0.011444091796875],
  [3954664800, 0.011444091796875],
  [3986287200, 0.011444091796875],
  [4017823200, 0.011444091796875],
  [4049359200, 0.0057220458984375],
  [4080895200, 0.0057220458984375],
  [4112431200, 0.0057220458984375],
  [4143967200, 0.0057220458984375],
  [4175503200, 0.0028610229492188],
  [4207039200, 0.0028610229492188],
  [4238661600, 0.0028610229492188],
  [4270197600, 0.0028610229492188],
  [4301733600, 0.0014305114746094],
  [4333269600, 0.0014305114746094],
  [4364892000, 0.0014305114746094],
  [4396428000, 0.0014305114746094],
  [4427964000, 0.0007152557373047],
  [4459500000, 0.0007152557373047],
  [4491122400, 0.0007152557373047],
  [4522658400, 0.0007152557373047],
  [4554194400, 0.00035762786865235],
  [4585730400, 0.00035762786865235],
  [4617352800, 0.00035762786865235],
  [4648888800, 0.00035762786865235]
];

第1列代表时间戳，每个代表未来100年每年的日期26.04，第2列基本上是每4年减半的值。必须在第2列的所有值之间计算加权平均值，并且将每个值计入计算的次数就是该值的权重。我必须应用的条件是我从用户输入中获取的日期，并且我只需要计算与所有小于用户输入所给日期的时间戳相对应的值。我不知道从哪里开始。

Answer 1

您可以filter小于输入日期的日期，然后使用reduce

计算index = 1处的平均值。

var timestamp=[[1524751200,6000],[1556287200,6000],[1587909600,6000],[1619445600,6000],[1650981600,3000],[1682517600,3000],[1714140000,3000],[1745676000,3000],[1777212000,1500],[1808748000,1500],[1840370400,1500],[1871906400,1500],[1903442400,750],[1934978400,750],[1966600800,750],[1998136800,750],[2029672800,375],[2061208800,375],[2092831200,375],[2124367200,375],[2155903200,187.5],[2187439200,187.5],[2219061600,187.5],[2250597600,187.5],[2282133600,93.75],[2313669600,93.75],[2345292000,93.75],[2376828000,93.75],[2408364000,46.875],[2439900000,46.875],[2471522400,46.875],[2503058400,46.875],[2534594400,23.4375],[2566130400,23.4375],[2597752800,23.4375],[2629288800,23.4375],[2660824800,11.71875],[2692360800,11.71875],[2723983200,11.71875],[2755519200,11.71875],[2787055200,5.859375],[2818591200,5.859375],[2850213600,5.859375],[2881749600,5.859375],[2913285600,2.9296875],[2944821600,2.9296875],[2976444000,2.9296875],[3007980000,2.9296875],[3039516000,1.46484375],[3071052000,1.46484375],[3102674400,1.46484375],[3134210400,1.46484375],[3165746400,0.732421875],[3197282400,0.732421875],[3228904800,0.732421875],[3260440800,0.732421875],[3291976800,0.3662109375],[3323512800,0.3662109375],[3355135200,0.3662109375],[3386671200,0.3662109375],[3418207200,0.18310546875],[3449743200,0.18310546875],[3481365600,0.18310546875],[3512901600,0.18310546875],[3544437600,0.091552734375],[3575973600,0.091552734375],[3607596000,0.091552734375],[3639132000,0.091552734375],[3670668000,0.0457763671875],[3702204000,0.0457763671875],[3733826400,0.0457763671875],[3765362400,0.0457763671875],[3796898400,0.02288818359375],[3828434400,0.02288818359375],[3860056800,0.02288818359375],[3891592800,0.02288818359375],[3923128800,0.011444091796875],[3954664800,0.011444091796875],[3986287200,0.011444091796875],[4017823200,0.011444091796875],[4049359200,0.0057220458984375],[4080895200,0.0057220458984375],[4112431200,0.0057220458984375],[4143967200,0.0057220458984375],[4175503200,0.0028610229492188],[4207039200,0.0028610229492188],[4238661600,0.0028610229492188],[4270197600,0.0028610229492188],[4301733600,0.0014305114746094],[4333269600,0.0014305114746094],[4364892000,0.0014305114746094],[4396428000,0.0014305114746094],[4427964000,0.0007152557373047],[4459500000,0.0007152557373047],[4491122400,0.0007152557373047],[4522658400,0.0007152557373047],[4554194400,0.00035762786865235],[4585730400,0.00035762786865235],[4617352800,0.00035762786865235],[4648888800,0.00035762786865235]];

const calculateAverage = (date) => {
  const filter = timestamp.filter(a => a[0] * 1000 < new Date(date));
  const average = filter.reduce((r,a) => r + a[1], 0) / filter.length;
  return average;
}

console.log(calculateAverage("10/10/2023"))

在1000中，filter有一个乘法，因为您提到了这些是将来的日期。因此，我假设第一列以秒而不是毫秒为单位

使用JavaScript从2d数组计算加权平均值

1 个答案: