Ndtyjky

I have array of objects like this

var a = [

 {'time' : 1539664755070,'T-1': 23 },

 {'time' : 1539665095442,'H-1': 24 },

 {'time' : 1539666489560,'T-1': 42 },

 {'time' : 1539665095442,'H-1': 27 },

 {'time': 1539671682230,'H-1': 40.45,'T-2': 33},

 {'time': 1539671682230,'T-2': 30.45,'T-1': 65},

 {'time': 1539671682230,'T-2': 42.45,'H-1': 11},

 {'time': 1539671682230,'T-1': 50.45,'T-2': 85}

];

I want to have data like this

data : {

  'T-1' : [23,42,50.45],

  'T-2' : [33,30.45,85],

  'H-1' : [24,27,40.45,11]

}

How can i get this data from given data?

Here is a solution, if something is not clear, please lemme know:

const result = {};



a.forEach(object => {

    // Loop on each entry in the original array

    Object.entries(object).forEach(([key,value]) => {

      // Loop through each entry of one entry of the original array 

      // (ex 'T-1', 'T-2')

      if(key !== 'time') {

        // It's a key that I'm interested in, so do logic

        if(!result[key]) {

          // If the key (example 'T-1') haven't been encountered yet, 

          // initialize it's entry in the result with an empty array

          result[key] = ;

        }

        result[key].push(value);

      }  

    });

});

Best use case for using Map instead of Key,Value arrays. Simplifies lot of things.

You can use array#reduce with Object.values() to create a hash of your key and add the values corresponding to it. Then using Object.assign() and spread syntax you can create the final object.

let data = [ {'time' : 1539664755070,'T-1': 23 }, {'time' : 1539665095442,'H-1': 24 }, {'time' : 1539666489560,'T-1': 42 }, {'time' : 1539665095442,'H-1': 27 }, {'time': 1539671682230,'H-1': 40.45,'T-2': 33}, {'time': 1539671682230,'T-2': 30.45,'T-1': 65},{'time': 1539671682230,'T-2': 42.45,'H-1': 11}, {'time': 1539671682230,'T-1': 50.45,'T-2': 85} ],

  result = Object.assign({}, ...Object.values(data.reduce((r, o) => {

    let keys = Object.keys(o).filter(k => k !== 'time');

    keys.forEach(key => {

      r[key] = r[key] || {[key] : };

      r[key][key].push(o[key]);

    });

    return r;

  },{})));

console.log(result);

const data = a.reduce((acc, row) => {

  // Loop over keys of each row.

  Object.keys(row)

    // Filter out the "time" keys.

    .filter((key) => key !== 'time')

    // Collect the values by key, storing them in the accumulator.

    .forEach((key) => {

      if (typeof acc[key] === 'undefined') {

        acc[key] = 

      }



      acc[key].push(row[key])

    })



  return acc

}, {})