Question

I got an array with different school grades. This data is gathered from a json file. In this array there are also grades that are 0. These are grades from students that didn’t complete the course. I want to remove all the 0 in the array, but I have no idea how to start.

example of the array:

var grades = [7,6,4,0,4,8,9,6,6,10,0,7,8,6,7]

p.s. I’m using d3

Answer 1

You can try Array.filter:

var nonzero = grades.filter(function(v) {
    return v !== 0;
});

As commenteers correctly noted, .filter is not avail in all browsers. You can use the shim available on MDN (see link above), or re-write your code to something like this:

var i=0, len = grades.length, nonzero = [];
for(;i<len;i++) {
    grades[i] !== 0 && nonzero.push(grades[i]);
}