How to sum the values of a JavaScript object?

Question

I\'d like to sum the values of an object.

I\'m used to python where it would just be:

sample = { \'a\': 1 , \'b\': 2 , \'c\':3 };
summed =  sum(sampl         


        

Answer 1

You could put it all in one function:

function sum( obj ) {
  var sum = 0;
  for( var el in obj ) {
    if( obj.hasOwnProperty( el ) ) {
      sum += parseFloat( obj[el] );
    }
  }
  return sum;
}
    
var sample = { a: 1 , b: 2 , c:3 };
var summed = sum( sample );
console.log( "sum: "+summed );

---

For fun's sake here is another implementation using Object.keys() and Array.reduce() (browser support should not be a big issue anymore):

function sum(obj) {
  return Object.keys(obj).reduce((sum,key)=>sum+parseFloat(obj[key]||0),0);
}
let sample = { a: 1 , b: 2 , c:3 };

console.log(`sum:${sum(sample)}`);

But this seems to be way slower: jsperf.com