js array of arrays take rows code example
Example: javascript array column
//get column in javascript...
function getCol(matrix, col){
var column = [];
for(var i=0; i<matrix.length; i++){
column.push(matrix[i][col]);
}
return column; // return column data..
}
var array = [new Array(20), new Array(20), new Array(20)]; //..your 3x20 array
getCol(array, 0); //Get first column