[Solved]-How to merge objects using javascript-d3.js

Can you use lodash?

var names = {
  'characters': [
    { 'name': 'barney' },
    { 'name': 'fred' }
  ]
};

var ages = {
  'characters': [
    { 'age': 36 },
    { 'age': 40 }
  ]
};

_.merge(names, ages);
// → { 'characters': [{ 'name': 'barney', 'age': 36 }, { 'name': 'fred', 'age': 40 }] }

var food = {
  'fruits': ['apple'],
  'vegetables': ['beet']
};

var otherFood = {
  'fruits': ['banana'],
  'vegetables': ['carrot']
};

_.merge(food, otherFood, function(a, b) {
  return _.isArray(a) ? a.concat(b) : undefined;
});
// → { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot] }