How Do I Pivot An Array Of Objects in JavaScript? -

i have array of object need convert table (kind of pivoting data). saying need array of objects unique titles have nested arrays of object pairs of values. please take , achiving need? please see original , desired array below:

original array:

[ {title: "title1", value1: "value1", value2: "value2"}, {title: "title2", value1: "value1", value2: "value2"}, {title: "title1", value1: "value1", value2: "value2"}, {title: "title3", value1: "value1", value2: "value2"}, {title: "title2", value1: "value1", value2: "value2"}, {title: "title1", value1: "value1", value2: "value2"}, {title: "title3", value1: "value1", value2: "value2"}, {title: "title1", value1: "value1", value2: "value2"}, ] 

desired result:

[ {title: "title1", values: [{value1: "value1"}, {value2: "value2"}]}, {title: "title2", values: [{value1: "value1"}, {value2: "value2"}]}, {title: "title3", values: [{value1: "value1"}, {value2: "value2"}]}, ] 

thanks if advance suggestions.

you use hash table grouping thisarg array#foreach.

var data = [{ title: "title1", value1: "value1", value2: "value2" }, { title: "title2", value1: "value1", value2: "value2" }, { title: "title1", value1: "value1", value2: "value2" }, { title: "title3", value1: "value1", value2: "value2" }, { title: "title2", value1: "value1", value2: "value2" }, { title: "title1", value1: "value1", value2: "value2" }, { title: "title3", value1: "value1", value2: "value2" }, { title: "title1", value1: "value1", value2: "value2" }],      grouped = [];    data.foreach(function (a) {        // check if title not in hash table      if (!this[a.title]) {            // if not, create new object title , values array          // , assign title hash hash table          this[a.title] = { title: a.title, values: [] };            // add new object result set,          grouped.push(this[a.title]);      }        // create new object other values , push      // array of object of hash table      this[a.title].values.push({ value1: a.value1, value2: a.value2 });  }, object.create(null)); // object.create creates empty object without prototypes    console.log(grouped);

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