How to subtract one array from another, element-wise, in javascript

Question

If i have an array A = [1, 4, 3, 2] and B = [0, 2, 1, 2] I want to return a new array (A - B) with values [1, 2, 2, 0]. What is the most e

Answer 1

Use map method The map method takes three parameters in it's callback function like below

currentValue, index, array

var a = [1, 4, 3, 2],
  b = [0, 2, 1, 2]

var x = a.map(function(item, index) {
  // In this case item correspond to currentValue of array a, 
  // using index to get value from array b
  return item - b[index];
})
console.log(x);