Set a custom % of 1's into a 2D blank array, where the 1's are randomly shuffled?

I've been a long time lurker on Stack Overflow but I couldn't seem to find a suitable existing solution...

I'm learning JS and HTML, and I've been playing around with 2D arrays to make game board. So far I made a custom # of rows/columns for a game board with all white tiles (represented as 0 for now).

My goal is to use an input field for a % of black tiles (represented as 1) to fill up the board (2D Array), but the black tiles have to be randomly distributed/shuffled among it.

Here's what I've got so far..

http://ift.tt/2c6WQbi

function generateArray() {

var myNode = document.getElementById("table");
while (myNode.firstChild) {
    myNode.removeChild(myNode.firstChild);
}

rows = $("#rows-field").val();
cols = $("#cols-field").val();

concentration = $("#concentration-field").val()
source = $("#source-field").val();
target = $("#target-field").val();



var table = document.getElementById("table");
for (var i = 0; i < rows; i++) {
    var tr = document.createElement('tr');
    for (var j = 0; j < cols; j++) {
        var td = document.createElement('td');
        if (i%2 == j%2) {
            td.className = "white";
        } else {
            td.className = "black";
        }
        tr.appendChild(td);
    }
    table.appendChild(tr);
}
document.body.appendChild(table);


}

Thanks in advance for any help or advice.