Creating Tally

tally

//From Reduce - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce?v=a
//Counting instances of values in an object
//Initializing with an empty object

var names = ['Alice', 'Bob', 'Tiff', 'Bruce', 'Alice'];

var countedNames = names.reduce(function (allNames, name) { 
  if (name in allNames) {
    allNames[name]++;
  }
  else {
    allNames[name] = 1;
  }
  return allNames;
}, {});
// countedNames is:
// { 'Alice': 2, 'Bob': 1, 'Tiff': 1, 'Bruce': 1 }