/*****************************************************************/
/**			       												**/
/**	ARTLIB.C													**/
/**		general library functions for ART model					**/
/**																**/
/**						Takehisa Tanaka							**/
/**						M.R.I.T.								**/
/**						1991/08/06								**/
/*****************************************************************/
#include "nsl_include.h"

/*****************************************************************/
/**	matrix_by_vector()											**/
/**		multiply matrix by vector								**/
/**						1991/08/06								**/
/*****************************************************************/
NslInt1	matrix_by_vector(NslInt2& mat,NslInt1& vec)
{
    int		m,n;
    int		x,y;

    /* Checking the matrix and vector size */
    m = mat.get_xn();
    n = mat.get_yn();
    if (n != vec.get_xn()) {
		cerr << "Oops! It seems error in matrix_by_vector().\n";
		exit(-1);
    }

    NslInt1	tmp_vector(m);
    tmp_vector = 0;

    for (x = 0;x < m;x++)
		for (y = 0;y < n;y++)
			tmp_vector.elem(x) += mat.elem(x,y) * vec.elem(y);

    return tmp_vector;
}

/*****************************************************************/
/**	uniform_random()											**/
/**	        return random value according to uniform			**/
/**		distribution											**/
/**						1991/08/06								**/
/*****************************************************************/
float uniform_random(float min,float max)
{
	const double MAX_RAND = 2147483648.0; /* maximum generated by rand() */

    float tmp;

    max = max - min;
//   tmp = (double) random() / MAX_RAND; // taken out AW 3/11/97
     tmp = (double) rand() / MAX_RAND; // added AW 3/11/97
    tmp *= max;
    tmp += min;

    return tmp;
}

/*****************************************************************/
/**	vector_matrix()												**/
/**	        Transform nsl_vector into nsl_matrix				**/
/**						1991/08/09								**/
/*****************************************************************/
int	vector_matrix(NslInt1& vec,NslInt2& mat)
{
    int		size,x_size,y_size;
    int		i,x,y;

    size = vec.get_xn();
    x_size = mat.get_xn();
    y_size = mat.get_yn();

    if (size != x_size * y_size) {
		cerr << "vector can't be transformed into matrix!!\n";
		cerr << "in vector_matrix().\n";
	return -1;
    }


    i = 0;
    for (x = 0;x < x_size;x++) { // reversed x,y
        for (y = 0; y < y_size;y++) {
			mat.elem(x,y) = vec.elem(i);
			i++;
		}
    }
    return 0;
}
       
/*****************************************************************/
/**	matrix_vector()												**/
/**	        Transform nsl_vector into nsl_matrix				**/
/**						1991/08/09								**/
/*****************************************************************/
int	matrix_vector(NslInt2& mat,NslInt1& vec)
{
    int		size,x_size,y_size;
    int		i,x,y;

    size = vec.get_xn();
    x_size = mat.get_xn();
    y_size = mat.get_yn();

    if (size != x_size * y_size) {
		cerr << "vector can't be transformed into matrix!!\n";
		cerr << "in matrix_vector().\n";
		return -1;
    }

    i = 0;
    for (x = 0;x < x_size;x++) { // reversed x,y
        for (y = 0; y < y_size;y++) {
			vec.elem(i) = mat.elem(x,y);
			i++;
		}
    }
    return 0;
}