turn into 2d array index

Question

I have a array with 3*3 dimension(2d) like this:

a[3][3]=[[1,2,3],[4,5,6],[7,8,9]];

I want formulate this array to access in single array(1d). how I can do this? like:

 b[9]=[0,1,2,3,4,5,6,7,8,9];

Answer 1

you want to convert a 2d array to a flat array. How about:

var a = [[1,2,3],[4,5,6],[7,8,9]];
var merged = [];
merged = merged.concat.apply(merged, a);

see https://stackoverflow.com/a/10865042/1432801

Answer 2

var flatArray = [];
for(var i=0;i<a.length;i++){
    for(var j=0;j<a[i].length;j++){
        flatArray.push(a[i][j]);
    }
}