javascript - Sum similar keys in an array of objects -

i have array of objects following: -

[     {         'name': 'p1',         'value': 150     },     {         'name': 'p1',         'value': 150     },     {         'name': 'p2',         'value': 200     },     {         'name': 'p3',         'value': 450     } ] 

i need add (summation) , other mathematical operation calculate average object same name appearing in it. like: -

[     {         'name': 'p1',         'value': 300     },     {         'name': 'p2',         'value': 200     },     {         'name': 'p3',         'value': 450     } ] 

would appreciate can get.

thanks in advance!

first iterate through array , push 'name' object's property. if property exists add 'value' value of property otherwise initialize property 'value'. once build object, iterate through properties , push them array.

here code:

var obj = [     { 'name': 'p1', 'value': 150 },     { 'name': 'p1', 'value': 150 },     { 'name': 'p2', 'value': 200 },     { 'name': 'p3', 'value': 450 } ];  var holder = {};  obj.foreach(function (d) {     if(holder.hasownproperty(d.name)) {        holder[d.name] = holder[d.name] + d.value;     } else {               holder[d.name] = d.value;     } });  var obj2 = [];  for(var prop in holder) {     obj2.push({name: prop, value: holder[prop]});    }  console.log(obj2); 

hope helps.