Javascript algorithm to find elements in array that are not in another array

Question

I'm looking for a good algorithm to get all the elements in one array that are not elements in another array. So given these arrays:

var x = ["a","b","c","t"]; var ​​​​​​​​​y = [​​​​​​​"d","a","t","e","g"]; 

I want to end up with this array:

var z = ["d","e","g"]; 

I'm using jquery, so I can take advantage of $.each() and $.inArray(). Here's the solution I've come up with, but it seems like there should be a better way.

// goal is to get rid of values in y if they exist in x var x = ["a","b","c","t"]; var y = ["d","a","t","e","g"];  var z = []; $.each(y, function(idx, value){   if ($.inArray(value,x) == -1) {     z.push(value);   } }); ​alert(z);  // should be ["d","e","g"] 

Here is the code in action. Any ideas?

Answer 1

in ES6 simply

const a1 = ["a", "b", "c", "t"]; const a2 = ["d", "a", "t", "e", "g"];  console.log( a2.filter(x => !a1.includes(x)) );

(another option is a2.filter(x => a1.indexOf(x)===-1) )