javascript - 根据元素出现的频率对数组进行排序

Question

我有一个包含重复数据的数组。我想根据频率对其进行排序(首先是最高的重复元素)，然后删除重复项。

我尝试了下面的代码，它抛出了不同的顺序。

var arr=[
    {name: "Manage AAA Devices", sys_id: "7b491aad371adb003ef7a9c2b3990e22"},
    {name: "", sys_id: ""},
    {name: "Manage AAA - ISE Admin Functions", sys_id: "dc5f99a2dbb2b74019d81ffa68961933"},
    {name: "Manage AAA Devices", sys_id: "7b491aad371adb003ef7a9c2b3990e22"},
    {name: "Manage AAA - ISE Admin Functions", sys_id: "dc5f99a2dbb2b74019d81ffa68961933"},
    {name: "SNOW Change Request", sys_id: "325b08913783d6c4f4f4c97a43990e90"},
    {name: "", sys_id: ""},
    {name: "Manage AAA - ISE Admin Functions", sys_id: "dc5f99a2dbb2b74019d81ffa68961933"},
    {name: "Manage AAA - ISE Admin Functions", sys_id: "dc5f99a2dbb2b74019d81ffa68961933"},
    {name: "Incident Request", sys_id: "3ee543f61b363740f713ed7b2f4bcbc0"}
];

console.log(arr.reduce((x, y) => {
  if (x[y.name]) {
    x[y.name]++;
    return x;
  } else {
    var z = {};
    z[y.name] = 1;
    return Object.assign(x, z);
  }
}, {}))

Answer 1

不是最佳解决方案，但您可以将其用作开始:

var arr = [{
    "name": "Manage AAA Devices",
    "sys_id": "7b491aad371adb003ef7a9c2b3990e22"
  },
  {
    "name": "",
    "sys_id": ""
  },
  {
    "name": "Manage AAA - ISE Admin Functions",
    "sys_id": "dc5f99a2dbb2b74019d81ffa68961933"
  },
  {
    "name": "Manage AAA Devices",
    "sys_id": "7b491aad371adb003ef7a9c2b3990e22"
  },
  {
    "name": "Manage AAA - ISE Admin Functions",
    "sys_id": "dc5f99a2dbb2b74019d81ffa68961933"
  },
  {
    "name": "SNOW Change Request",
    "sys_id": "325b08913783d6c4f4f4c97a43990e90"
  },
  {
    "name": "",
    "sys_id": ""
  },
  {
    "name": "Manage AAA - ISE Admin Functions",
    "sys_id": "dc5f99a2dbb2b74019d81ffa68961933"
  },
  {
    "name": "Manage AAA - ISE Admin Functions",
    "sys_id": "dc5f99a2dbb2b74019d81ffa68961933"
  },
  {
    "name": "Incident Request",
    "sys_id": "3ee543f61b363740f713ed7b2f4bcbc0"
  }
];

const noOfOccurencies = arr.reduce((x, y) => {
  if (x[y.name]) {
    x[y.name]++;
    return x;
  } else {
    var z = {};
    z[y.name] = 1;
    return Object.assign(x, z);
  }
}, {})

console.log(noOfOccurencies);

// Order an array of objects based on another array order
// https://gist.github.com/ecarter/1423674
function mapOrder(array, order, key) {
  array.sort(function(a, b) {
    var A = a[key],
      B = b[key];

    if (order.indexOf(A) > order.indexOf(B)) {
      return 1;
    } else {
      return -1;
    }
  });
  return array;
};

// sort noOfOccurencies
const itemOrder = Object.keys(noOfOccurencies).sort(function(a, b) {
  return noOfOccurencies[a] - noOfOccurencies[b]
})
// reverse noOfOccurencies (*highest duplicates element first*)
itemOrder.reverse();

console.log(itemOrder);

// order the original array based on itemOrder
let ordered_array = mapOrder(arr, itemOrder, 'name');

// remove duplicates from the new array ordered
const noDuplicatesArr = ordered_array.filter((v, i, a) => a.findIndex(t => (t.name === v.name)) === i)

console.log(noDuplicatesArr);