jquery - Javascript groupby week/month/year -

i have json array data in it. i'd group data in week, month & year.

i tried following discussion javascript groupby

how can sum of values grouped month & year in expected output show below please?

following example quoted, output below

monthly grouping's output

yearly grouping's output

here's data & code

function displaycalc() {     var data= [{             "event_date": "2015-06-27",             "number_events": 3,             "full_event_duration": 42.24,             "first_pause": 42.24,             "second_pause": 14.08,             "third_pause": 42.24,             "fourth_pause": 42.24,             "fifth_pause": 42.24,             "sixth_pause": 42.24         }, {             "event_date": "2015-06-28",             "number_events": 3,             "full_event_duration": 27.54,             "first_pause": 27.54,             "second_pause": 9.18,             "third_pause": 27.54,             "fourth_pause": 27.54,             "fifth_pause": 27.54,             "sixth_pause": 27.54         },{             "event_date": "2015-07-02",             "number_events": 39,             "full_event_duration": 354.39,             "first_pause": 26.19,             "second_pause": 9.08,             "third_pause": 29.96,             "fourth_pause": 32.79,             "fifth_pause": 35,             "sixth_pause": 36.47         }, {             "event_date": "2015-07-03",             "number_events": 66,             "full_event_duration": 593,             "first_pause": 26.26,             "second_pause": 8.98,             "third_pause": 29.21,             "fourth_pause": 31.24,             "fifth_pause": 33.21,             "sixth_pause": 34.56         },{             "event_date": "2015-08-01",             "number_events": 6,             "full_event_duration": 57.21,             "first_pause": 28.6,             "second_pause": 9.53,             "third_pause": 35.33,             "fourth_pause": 36.17,             "fifth_pause": 36.68,             "sixth_pause": 37.02         }, {             "event_date": "2015-08-02",             "number_events": 12,             "full_event_duration": 94.47,             "first_pause": 23.22,             "second_pause": 7.87,             "third_pause": 25.1,             "fourth_pause": 25.36,             "fifth_pause": 25.51,             "sixth_pause": 25.62         }, {             "event_date": "2015-09-01",             "number_events": 12,             "full_event_duration": 88.55,             "first_pause": 6.84,             "second_pause": 7.37,             "third_pause": 9.18,             "fourth_pause": 9.82,             "fifth_pause": 10.21,             "sixth_pause": 10.48         }, {             "event_date": "2015-09-03",             "number_events": 15,             "full_event_duration": 116.13,             "first_pause": 6.95,             "second_pause": 7.74,             "third_pause": 9.52,             "fourth_pause": 10.99,             "fifth_pause": 12.39,             "sixth_pause": 13.33         }];       var grouped = _.groupby(data, function (item) {         return item.event_date;     });      var groupedbyyear = _.groupby(data, function (item) {         return item.event_date.substring(0, 4);     });      var groupedbymonth = _.groupby(data, function (item) {         return item.event_date.substring(0, 7);     });      console.log(grouped);     console.log(groupedbyyear);     console.log(groupedbymonth); } 

could request achieve please?

the output generated below

weekly aggregated data

     var jsondata = [{     "event_date": "2015-01-04",     "number_events": 30,     "full_event_duration": 100.27,     "first_pause": 142.24,     "second_pause": 143.08,     "third_pause": 305.24,     "fourth_pause":271.24,     "fifth_pause": 289.24,     "sixth_pause": 238.24   }, {     "event_date": "2015-01-11",     "number_events": 300,     "full_event_duration": 131.27,     "first_pause": 124.24,     "second_pause": 347.08,     "third_pause": 245.24,     "fourth_pause":345.24,     "fifth_pause": 168.24,     "sixth_pause": 458.24   }, {     "event_date": "2015-01-18",     "number_events": 49,     "full_event_duration": 456.27,     "first_pause": 23.24,     "second_pause": 37.08,     "third_pause": 678.24,     "fourth_pause":345.24,     "fifth_pause": 123.24,     "sixth_pause": 123.24   }] 

monthly aggregated data

   var jsondata = [{     "event_date": "2015-01",     "number_events": 30,     "full_event_duration": 100.27,     "first_pause": 142.24,     "second_pause": 143.08,     "third_pause": 305.24,     "fourth_pause":271.24,     "fifth_pause": 289.24,     "sixth_pause": 238.24   }, {     "event_date": "2015-02",     "number_events": 300,     "full_event_duration": 131.27,     "first_pause": 124.24,     "second_pause": 347.08,     "third_pause": 245.24,     "fourth_pause":345.24,     "fifth_pause": 168.24,     "sixth_pause": 458.24   }, {     "event_date": "2015-04",     "number_events": 49,     "full_event_duration": 456.27,     "first_pause": 23.24,     "second_pause": 37.08,     "third_pause": 678.24,     "fourth_pause":345.24,     "fifth_pause": 123.24,     "sixth_pause": 123.24   }]  

yearly aggregated data

       var jsondata = [{     "event_date": "2014",     "number_events": 3000,     "full_event_duration": 1000.27,     "first_pause": 1420.24,     "second_pause": 1430.08,     "third_pause": 3050.24,     "fourth_pause":2710.24,     "fifth_pause": 2890.24,     "sixth_pause": 2380.24   }, {     "event_date": "2015",     "number_events": 4000,     "full_event_duration": 131.27,     "first_pause": 1240.24,     "second_pause": 3470.08,     "third_pause": 2450.24,     "fourth_pause":3450.24,     "fifth_pause": 1680.24,     "sixth_pause": 4580.24   }] 

you have nothing defined data in code. should doing like.

var jsondata = [{             "event_date": "2015-06-27",             "number_events": 3,             "full_event_duration": 42.24,             "first_pause": 42.24,             "second_pause": 14.08,             "third_pause": 42.24,             "fourth_pause": 42.24,             "fifth_pause": 42.24,             "sixth_pause": 42.24         }, {             "event_date": "2015-06-28",             "number_events": 3,             "full_event_duration": 27.54,             "first_pause": 27.54,             "second_pause": 9.18,             "third_pause": 27.54,             "fourth_pause": 27.54,             "fifth_pause": 27.54,             "sixth_pause": 27.54         },{             "event_date": "2015-07-02",             "number_events": 39,             "full_event_duration": 354.39,             "first_pause": 26.19,             "second_pause": 9.08,             "third_pause": 29.96,             "fourth_pause": 32.79,             "fifth_pause": 35,             "sixth_pause": 36.47         }, {             "event_date": "2015-07-03",             "number_events": 66,             "full_event_duration": 593,             "first_pause": 26.26,             "second_pause": 8.98,             "third_pause": 29.21,             "fourth_pause": 31.24,             "fifth_pause": 33.21,             "sixth_pause": 34.56         },{             "event_date": "2015-08-01",             "number_events": 6,             "full_event_duration": 57.21,             "first_pause": 28.6,             "second_pause": 9.53,             "third_pause": 35.33,             "fourth_pause": 36.17,             "fifth_pause": 36.68,             "sixth_pause": 37.02         }, {             "event_date": "2015-08-02",             "number_events": 12,             "full_event_duration": 94.47,             "first_pause": 23.22,             "second_pause": 7.87,             "third_pause": 25.1,             "fourth_pause": 25.36,             "fifth_pause": 25.51,             "sixth_pause": 25.62         }, {             "event_date": "2015-09-01",             "number_events": 12,             "full_event_duration": 88.55,             "first_pause": 6.84,             "second_pause": 7.37,             "third_pause": 9.18,             "fourth_pause": 9.82,             "fifth_pause": 10.21,             "sixth_pause": 10.48         }, {             "event_date": "2015-09-03",             "number_events": 15,             "full_event_duration": 116.13,             "first_pause": 6.95,             "second_pause": 7.74,             "third_pause": 9.52,             "fourth_pause": 10.99,             "fifth_pause": 12.39,             "sixth_pause": 13.33         }];  var grouped = _.groupby(jsondata, function (item) {     return item.event_date; });  var groupedbyyear = _.groupby(jsondata, function (item) {     return item.event_date.substring(0, 4); });  var groupedbymonth = _.groupby(jsondata, function (item) {     return item.event_date.substring(0, 7); });  console.log(grouped); console.log(groupedbyyear); console.log(groupedbymonth); //to desired result can write in function var groupedarray=[]; ( key in groupedbymonth){ var obj = {}; obj.event_date=key; obj.fifth_pause=0; obj.first_pause=0; obj.fourth_pause=0; obj.full_event_duration=0; obj.number_events=0; obj.second_pause=0; obj.sixth_pause=0; obj.third_pause=0;   for(var i=0;i<groupedbymonth[key].length;i++){     obj.fifth_pause+=groupedbymonth[key][i].fifth_pause;     obj.first_pause+=groupedbymonth[key][i].first_pause;     obj.fourth_pause+=groupedbymonth[key][i].fourth_pause;     obj.full_event_duration+=groupedbymonth[key][i].full_event_duration;     obj.number_events+=groupedbymonth[key][i].number_events;     obj.second_pause+=groupedbymonth[key][i].second_pause;     obj.sixth_pause+=groupedbymonth[key][i].sixth_pause;     obj.third_pause+=groupedbymonth[key][i].third_pause;   }       obj.fifth_pause=(obj.fifth_pause/groupedbymonth[key].length).tofixed(2);     obj.first_pause=(obj.first_pause/groupedbymonth[key].length).tofixed(2);     obj.fourth_pause=(obj.fourth_pause).tofixed(2);     obj.full_event_duration=(obj.full_event_duration/groupedbymonth[key].length).tofixed(2);     obj.number_events=(obj.number_events/groupedbymonth[key].length).tofixed(2);     obj.second_pause=(obj.second_pause/groupedbymonth[key].length).tofixed(2);     obj.sixth_pause=(obj.sixth_pause/groupedbymonth[key].length).tofixed(2);     obj.third_pause=(obj.third_pause/groupedbymonth[key].length).tofixed(2);      groupedarray.push(obj); }  console.log(groupedarray)