Task

Build an   identity matrix   of a size known at run-time.



An identity matrix is a square matrix of size n × n,

where the diagonal elements are all 1s (ones),

and all the other elements are all 0s (zeroes).







I

n


=


[



1


0


0


⋯


0




0


1


0


⋯


0




0


0


1


⋯


0




⋮


⋮


⋮


⋱


⋮




0


0


0


⋯


1



]




{\displaystyle I_{n}={\begin{bmatrix}1&0&0&\cdots &0\\0&1&0&\cdots &0\\0&0&1&\cdots &0\\\vdots &\vdots &\vdots &\ddots &\vdots \\0&0&0&\cdots &1\\\end{bmatrix}}}





Related tasks

   Spiral matrix
   Zig-zag matrix 
   Ulam_spiral_(for_primes)


 
function identity(n) {
    if (n < 1) return "Not defined";
    else if (n == 1) return 1;
    else {
        var idMatrix:number[][];
        for (var i: number = 0; i < n; i++) {
            for (var j: number = 0; j < n; j++) {
                if (i != j) idMatrix[i][j] = 0;
                else idMatrix[i][j] = 1;
            }            
        }
        return idMatrix;
    }
}
 