Solve MxN system using LU Decomposition

LUSolveMxN.as

/**
* LU decomposition/solve is used for NxN (square) matrices
* but using additional computations we can use LU decomposition
* to solve MxN system (since LU routines less computation expensive)
*/

// u can find LU and MatrixMath Classes at my Google repo

var lu:LU = new LU();

// A:B - system
// m - rows; n - cols;
// x - solution 
function LUSolveMxN(A:Vector.<Number>, m:int, n:int, x:Vector.<Number>, B:Vector.<Number>):Boolean
{
	var At:Vector.<Number> = new Vector.<Number>((m*n), true);
	var AtA:Vector.<Number> = new Vector.<Number>((n*n), true);
	var AtB:Vector.<Number> = new Vector.<Number>(n, true);
			
	MatrixMath.transposeMat( A, At, m, n );
	MatrixMath.multMat( At, A, AtA, n, m, n );
	MatrixMath.multMat( At, B, AtB, n, m, 1);

	// bad matrix
	if( !lu.solve(AtA, n, x, AtB) ) return false;
	return true;
}