/* Eigen_and_Matrix.c
 *
 * Copyright (C) 2002 David Weenink
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 djmw 20020327 Initial version
*/

#include "Eigen_and_Matrix.h"

Matrix Eigen_and_Matrix_project (I, thou, long numberOfComponents)
{
	iam (Eigen);
	thouart (Matrix); 
	Matrix him = NULL;

	if (numberOfComponents == 0) numberOfComponents = my numberOfEigenvalues;

	him = Matrix_create (thy xmin, thy xmax, thy nx, thy dx, thy x1, 0.5, 0.5 +
		numberOfComponents, numberOfComponents, 1, 1);
	if (him != NULL)
	{
		if (! Eigen_and_Matrix_project_into (me, thee, & him)) forget (him);
	}
	return him;
}

int Eigen_and_Matrix_project_into (I, thou, Any void_pointer_to_him)
{
	Matrix him = *((Matrix *)void_pointer_to_him);
	thouart (Matrix);
	iam (Eigen);
	char *name = "Eigen_and_Matrix_project_into";
	long i, j, k;
	
	Melder_assert (him != NULL);
	
	if (my dimension != thy ny) return Melder_error
		("%s: The number of rows in the 'from' Matrix must equal "
			"the dimension of the eigenvector.", name);
	if (his nx != thy nx) return Melder_error
		("%s: The number of columns in the 'from' and the 'to' Matrix "
			"object must be equal.", name);
	if (his ny > my numberOfEigenvalues) return Melder_error
		("%s: The number of rows in the 'to' Matrix cannot exceed the "
			"number of eigenvectors.", name);

	for (i = 1; i <= thy nx; i++)
	{
		for (j = 1; j <= his ny; j++)
		{
			double r = 0;
			for (k = 1; k <= my dimension; k++)
			{
				/*
					eigenvector in row, data in column
				*/
				r += my eigenvectors[j][k] * thy z[k][i];
			}
			his z[j][i] = r;
		}
	}
	return 1;
}

/* End of file Eigen_and_Matrix.c */
