code: function(matrix) {
              	var M = matrix.elements || matrix;
              	if (typeof(M[0][0]) == 'undefined') { M = Matrix$b.create(M).elements; }
              	var T = this.dup(), cols = T.elements[0].length;
              	var i = T.elements.length, nj = M[0].length, j;
              	if (i != M.length) { return null; }
              	while (i--) {
              	    j = nj;
              	    while (j--) {
              		T.elements[i][cols + j] = M[i][j];
              	    }
              	}
              	return T;
                  }
docs: Returns the result of attaching the given argument to the right-hand side of the matrix