#include "SmallMatrix.h"

Functions
void	dgemv_ (const char trans, int m, int n, double alpha, double A, int LDA, double x, int incx, double beta, double y, int *incy)
	This does matrix times vector and is from blas level 2. More...

int	dgemm_ (const char transA, const char transB, int M, int N, int k, double alpha, double A, int LDA, double B, int LDB, double beta, double C, int *LDC)
	This is the gernal matrix multiplication from blas level 3. More...

int	daxpy_ (int N, double DA, double DX, int INCX, double DY, int INCY)
	This is the gerneral scalar times vector + vector from blas, hence from blas level 1. Here we also use on a matrix by treating as a vector. More...

void	dgetrf_ (int M, int N, double A, int lda, int IPIV, int INFO)
	This is LU factorisation of the matrix A. This has been taken from LAPACK. More...

void	dgetri_ (int N, double A, int lda, int IPIV, double WORK, int lwork, int *INFO)
	This is the inverse calulation also from LAPACK. Calculates inverse if you pass it the LU factorisation. More...

void	dgesv_ (int N, int NRHS, double A, int lda, int IPIV, double B, int LDB, int INFO)
	This is used for solve Ax=B for x. Again this is from LAPACK. More...

template<unsigned int numberOfRows, unsigned int numberOfColumns>
SmallVector< numberOfColumns >	operator* (SmallVector< numberOfRows > &vec, SmallMatrix< numberOfRows, numberOfColumns > &mat)
	Multiplies a matrix with a vector. More...

Function Documentation

◆ daxpy_()

int daxpy_	(	int *	N,
		double *	DA,
		double *	DX,
		int *	INCX,
		double *	DY,
		int *	INCY
	)

This is the gerneral scalar times vector + vector from blas, hence from blas level 1. Here we also use on a matrix by treating as a vector.

◆ dgemm_()

int dgemm_	(	const char *	transA,
		const char *	transB,
		int *	M,
		int *	N,
		int *	k,
		double *	alpha,
		double *	A,
		int *	LDA,
		double *	B,
		int *	LDB,
		double *	beta,
		double *	C,
		int *	LDC
	)

This is the gernal matrix multiplication from blas level 3.

Referenced by SmallMatrix< numberOfRows, numberOfColumns >::operator*().

◆ dgemv_()

void dgemv_	(	const char *	trans,
		int *	m,
		int *	n,
		double *	alpha,
		double *	A,
		int *	LDA,
		double *	x,
		int *	incx,
		double *	beta,
		double *	y,
		int *	incy
	)

This does matrix times vector and is from blas level 2.

Referenced by SmallMatrix< numberOfRows, numberOfColumns >::operator*(), and operator*().

◆ dgesv_()

void dgesv_	(	int *	N,
		int *	NRHS,
		double *	A,
		int *	lda,
		int *	IPIV,
		double *	B,
		int *	LDB,
		int *	INFO
	)

This is used for solve Ax=B for x. Again this is from LAPACK.

Referenced by SmallMatrix< numberOfRows, numberOfColumns >::solve().

◆ dgetrf_()

void dgetrf_	(	int *	M,
		int *	N,
		double *	A,
		int *	lda,
		int *	IPIV,
		int *	INFO
	)

This is LU factorisation of the matrix A. This has been taken from LAPACK.

Referenced by SmallMatrix< numberOfRows, numberOfColumns >::inverse(), and SmallMatrix< numberOfRows, numberOfColumns >::LUfactorisation().

◆ dgetri_()

void dgetri_	(	int *	N,
		double *	A,
		int *	lda,
		int *	IPIV,
		double *	WORK,
		int *	lwork,
		int *	INFO
	)

This is the inverse calulation also from LAPACK. Calculates inverse if you pass it the LU factorisation.

Referenced by SmallMatrix< numberOfRows, numberOfColumns >::inverse().

◆ operator*()

template<unsigned int numberOfRows, unsigned int numberOfColumns>

SmallVector<numberOfColumns> operator*	(	SmallVector< numberOfRows > &	vec,
		SmallMatrix< numberOfRows, numberOfColumns > &	mat
	)

Multiplies a matrix with a vector.

 {
     if (numberOfColumns == 0)
     {
         logger(WARN, "Trying to multiply a vector with a matrix without any columns.");
         return SmallVector<numberOfColumns>();
     }
     int nr = numberOfRows;
     int nc = numberOfColumns;
     
     int i_one = 1;
     double d_one = 1.0;
     double d_zero = 0.0;
     
     SmallVector<numberOfColumns> result;
     
     logger(DEBUG, "Matrix size: % x % \n Vector size: %", nr, nc, vec.size());
     
     dgemv_("T", &nr, &nc, &d_one, mat.data(), &nr, vec.data(), &i_one, &d_zero, result.data(), &i_one);
     return result;
 }

References Eigen::SparseMatrix< Scalar_, Options_, StorageIndex_ >::data(), SmallVector< numberOfRows >::data(), DEBUG, dgemv_(), logger, SmallVector< numberOfRows >::size(), and WARN.

Functions