allow seeding of V and added documentation

1 files changed, 76 insertions, 0 deletions

diff --git a/src/matrix.c b/src/matrix.c
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+++ b/src/matrix.c
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+/**
+ * @file matrix.c
+ * @author Gertjan van den Burg (burg@ese.eur.nl)
+ * @date August 8, 2013
+ * @brief Functions facilitating matrix access
+ *
+ * @details
+ * The functions contained in this file are used when
+ * accessing or writing to matrices. Seperate functions
+ * exist of adding and multiplying existing matrix
+ * elements, to ensure this is done in place.
+ *
+ */
+
+#include "matrix.h"
+
+/**
+ * @name matrix_set
+ * @brief Set element of matrix 
+ * @ingroup matrix
+ *
+ * Row-Major order is used to set a matrix element. Since matrices
+ * of type double are most common in MSVMMaj, this function only
+ * deals with that type.
+ *
+ * @param [in] 	M 	matrix to set element of
+ * @param [in]  cols 	number of columns of M
+ * @param [in] 	i 	row index of element to write to
+ * @param [in] 	j 	column index of element to write to
+ * @param [out] val 	value to write to specified element of M
+ */
+void matrix_set(double *M, long cols, long i, long j, double val)
+{
+	M[i*cols+j] = val;
+}
+
+double matrix_get(double *M, long cols, long i, long j)
+{
+	return M[i*cols+j];
+}
+
+void matrix_add(double *M, long cols, long i, long j, double val)
+{
+	M[i*cols+j] += val;
+}
+
+void matrix_mul(double *M, long cols, long i, long j, double val)
+{
+	M[i*cols+j] *= val;
+}
+
+void matrix3_set(double *M, long N2, long N3, long i, long j, 
+		long k, double val)
+{
+	M[k+N3*(j+N2*i)] = val;
+}
+
+double matrix3_get(double *M, long N2, long N3, long i, long j,
+		long k)
+{
+	return M[k+N3*(j+N2*i)];
+}
+
+
+void print_matrix(double *M, long rows, long cols)
+{
+	long i, j;
+
+	for (i=0; i<rows; i++) {
+		for (j=0; j<cols; j++)
+			info("%8.8f ", matrix_get(M, cols, i, j));
+		info("\n");
+	}
+	info("\n");
+}
+