Is it possible to define and initialize multidimensional arrays in JavaScript in one line of code?

You can use the literal syntax, but it would be very big and cumbersome. You may want to try something like this:

var x = [1, 1, 1, 1, 1, 1]; for (var i = 1; i < 4; i++) { x = [x, x, x, x, x, x]; } 

I found a slightly simpler solution:

var x = 1; for (var i = 0; i < 4; i++) { x = [x, x, x, x, x, x]; } 

Seems like there should be easier way, but this will do it.

var array = []; for(var i=0; i<6; i++) { for(var j=0; j<6; j++) { for(var k=0; k<6; k++) { for(var l=0; l<6; l++) { array[i][j][k][l]=1; } } } } 

Edit

To generate an n-dimensional AxBxCxDx... array (untested):

Array.prototype.fill = function(elem, n) { for(var i=0; i<n; i++, this.push(elem)); } function generateArray() { var dimensions = Array.prototype.slice.call(arguments); var x = 1; for (var i = dimensions.length-1; i >= 0; i--) { x = [].fill(x, dimensions[i]); } return x; } 

to generate a 2x3x4x5 matrix:

generateArray(2,3,4,5); 

I implemented ddlshack's generalized method, but ran into an issue due to the fact that arrays are "pass by reference" in JavaScript. This resulted in each dimension of the array holding multiple references to the same array rather than copies of it. To correct the issue, I implemented the solution as follows (the only other difference being that I used a second function rather than modify Array's prototype).

var fillArray = function(val, dim) { var a = []; for (var i = 0; i < dim; i++) { if (Object.prototype.toString.call(val) === "[object Array]") { val = val.slice(0); } a.push(val); } return a; }; var generateArray = function() { var dimensions = Array.prototype.slice.call(arguments), val = 0; for (var i = (dimensions.length - 1); i >= 0; i--) { val = fillArray(val, dimensions[i]); } return val; };