I have to find min value from an array of objects but I have multiple keys and I want to find the min value of all keys or specified keys.

For example

var users = [
    {id:"1", name:"ABC", age:30, height: 75, weight: 83},
    {id:"1", name:"ABC", age:24, height: 63, weight: 75},
    {id:"1", name:"ABC", age:27, height: 56, weight: 55}
]

In this example, I want to find the users with min age, height and weight. But by using a single function.

I am using this function. its finds min age only.

findMin(data) {
        return data.reduce((min, u) => u.age < min ? u.age : min, data[0].age);
    },

CodePudding user response：

You can try this :

const users = [ {id:"1", name:"ABC", age:30, height: 75, weight: 83}, {id:"1", name:"ABC", age:24, height: 63, weight: 75}, {id:"1", name:"ABC", age:27, height: 56, weight: 55} ];
const min = (arr, key) => arr.reduce((min, el) => el[key] < min[key] ? el : min);
const keys = ['age', 'height', 'weight'];
const result = Object.fromEntries(keys.map(k => [k, min(users, k)]));
console.log(result)

Using only 1 function :

const users = [ {id:"1", name:"ABC", age:30, height: 75, weight: 83}, {id:"1", name:"ABC", age:24, height: 63, weight: 75}, {id:"1", name:"ABC", age:27, height: 56, weight: 55} ];

const min = (arr, keys) => arr.reduce(
  (min, el) => Object.fromEntries(keys.map(k => [k, el[k] < min[k][k] ? el : min[k]])), 
  {age: arr[0], height: arr[0], weight: arr[0]}
 );

const result = min(users, ['age', 'height', 'weight']);
console.log(result)

Output :

{
    age: { minAgeItem },
    weight: { minWeightItem },
    height: { minHeightItem }
}

CodePudding user response：

This is my modified version!

const arr = [{
    id: "1",
    name: "ABC",
    age: 30,
    height: 75,
    weight: 83
  },
  {
    id: "1",
    name: "ABC",
    age: 24,
    height: 63,
    weight: 75
  },
  {
    id: "1",
    name: "ABC",
    age: 27,
    height: 56,
    weight: 55
  }
];

function getMins(array) {
  let minAge = Infinity,
    minHeight = Infinity,
    minWeight = Infinity;
  const output = [{}, {}, {}];
  array.forEach((user) => {
    if (user.age <= minAge) {
      minAge = user.age;
      output[0] = user;
    }
    if (user.height <= minHeight) {
      minHeight = user.height;
      output[1] = user;
    }
    if (user.weight <= minWeight) {
      minWeight = user.weight;
      output[2] = user;
    }

  });
  return output;
}

console.log(getMins(arr));

CodePudding user response：

I hope I understand you well, that you want to extract min value for each of fields. Then you could expand your functions to return an object like this:

Note: open chrome console and check output, SO console is giving some weird results!

var users = [
    {id:"1", name:"ABC", age:30, height: 75, weight: 83},
    {id:"1", name:"ABC", age:24, height: 63, weight: 75},
    {id:"1", name:"ABC", age:27, height: 56, weight: 55}
]

function findMin(data) {
  return data.reduce((mins, u) => {
    mins['minAge'] = (u.age < mins['minAge'] ? u.age : mins['minAge']);
    mins['minHeight'] = (u.height < mins['minHeight'] ? u.height : mins['minHeight']);
    mins['minWeight'] = (u.weight < mins['minWeight'] ? u.weight : mins['minWeight']);
    return mins
  }, {
    minAge: data[0].age,
    minHeight: data[0].height,
    minWeight: data[0].weight
  });
}

console.log(findMin(users))

edit: Added more flexibility to the function:

var users = [
{ id: "1", name: "ABC", age: 30, height: 75, weight: 83 },
  { id: "1", name: "ABC", age: 24, height: 63, weight: 75 },
  { id: "1", name: "ABC", age: 27, height: 56, weight: 55 }
];

function findMin(data, keys) {
  return data.reduce((mins, u) => {
    keys.forEach(
      (key) => (mins[key] = u[key] < mins[key] ? u[key] : mins[key])
    );
    return mins;
  }, keys.reduce((accumulator, value) => {
    return {...accumulator, [value]: data[0][value]};
  }, {}));
}

console.log(findMin(users, ['age','height']));

CodePudding user response：

Another one approach

const users = [
    {id:"1", name:"ABC", age:30, height: 75, weight: 83},
    {id:"2", name:"ABC", age:24, height: 63, weight: 75},
    {id:"3", name:"ABC", age:27, height: 56, weight: 55},
];

const getMinsBy = (users, properties) => {
  const minBy = (prop) => users.reduce((min, curr) => (min[prop] > curr[prop]) ? curr : min)
  
  return properties.reduce((acc, prop) => ({ ...acc, [prop]: minBy(prop) }), {});
};

console.log(getMinsBy(users, ['age', 'height', 'weight']));

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