Tripple_Pointer_Legacy

tpl.c

typedef double lr;

lr ***lr_3D_matrix(int m, int n, int o)/**  \brief create a 3D matrix with size [m, n,o] of type lr*/
{
	lr ***matrix;
	int i, j;
	matrix       =  malloc(m * sizeof(lr **));	    //allocate first dimension
	matrix[0]    =  malloc(m * n * sizeof(lr *));	//allocate continous memory block for all elements
	matrix[0][0] =  malloc(m * n * o * sizeof(lr)); //allocate memory for the whole matrix

// interleaving of pointers to make matrix[i][j][k] a valid 3d indexable array
	for(j = 1; j < n; j++)	//fill first row
	{
		matrix[0][j] = matrix[0][j - 1] + o;	//pointer to matrix[0][j][0], thus first element of matrix[0][j][o]
	}
	
	for(i = 1; i < m; ++i)
	{
		matrix[i] = matrix[i - 1] + n;	//pointer to position of  to matrix[i][0]
		matrix[i][0] = matrix[i - 1][n - 1] + o;	//pointer to  matrix[i][j][0];
		for(j = 1; j < n; ++j)
		{
			matrix[i][j] = matrix[i][j - 1] + o;
		}
	}
	return matrix;
}