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symmat_eigen.h File Reference

#include <gandalf/linalg/vec_gen.h>
#include <gandalf/linalg/mat_gen.h>
#include <gandalf/linalg/mat_square.h>

Go to the source code of this file.

Compounds
struct	Gan_SymMatEigenStruct
	Structure for eigendecomposition of an accumulated symmetric matrix. More...
Functions
Gan_SymMatEigenStruct *	gan_symeigen_form_data (Gan_SymMatEigenStruct *sme, long max_size, double *work_data, unsigned long work_data_size)
	Forms a symmetric matrix eigendecomposition structure.
Gan_SymMatEigenStruct *	gan_symeigen_form (Gan_SymMatEigenStruct *sme, long max_size)
	Macro: Forms a symmetric matrix eigendecomposition structure.
Gan_SymMatEigenStruct *	gan_symeigen_alloc (long max_size)
	Macro: Allocates a symmetric matrix eigendecomposition structure.
void	gan_symeigen_free (Gan_SymMatEigenStruct *sme)
	Frees a symmetric matrix eigendecomposition structure.
Gan_Bool	gan_symeigen_reset (Gan_SymMatEigenStruct *sme, long size)
	Initialises an accumulated outer product matrix to zero.
Gan_Bool	gan_symeigen_increment (Gan_SymMatEigenStruct *sme, double scale,...)
	Increments an accumulated outer product matrix.
Gan_Bool	gan_symeigen_solve (Gan_SymMatEigenStruct *sme)
	Eigendecomposes a matrix accumulated by summing outer products.

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Detailed Description

Module: Symmetric matrix eigenvalues & eigenvectors (double precision)

Part of: Gandalf Library

Revision: Last edited: Author:

Copyright: (c) 2000 Imagineer Software Limited

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Function Documentation

Gan_SymMatEigenStruct* gan_symeigen_form_data (  Gan_SymMatEigenStruct *    sme, long    max_size, double *    work_data, unsigned long    work_data_size )

Forms a symmetric matrix eigendecomposition structure. Parameters: sme  A pointer to a structure or NULL max_size  The envisaged largest size of matrix work_data  Workspace array for CLAPACK eigendecomposition work_data_size  Size of work_data array Returns: Pointer to structure, or NULL on failure. Allocates/fills a structure with initial values to compute the eigendecomposition of a sum of vector outer products. See also: gan_symeigen_form(), gan_symeigen_alloc().

void gan_symeigen_free (  Gan_SymMatEigenStruct *    sme )

Frees a symmetric matrix eigendecomposition structure. Parameters: sme  A pointer to a structure Returns: No value. Frees a structure created to compute the eigenvalues and eigenvectors of a symmetric matrix accumulated as a sum of vector outer products. See also: gan_symeigen_alloc().

Gan_Bool gan_symeigen_increment (  Gan_SymMatEigenStruct *    sme, double    scale, ...    )

Increments an accumulated outer product matrix. Parameters: sme  A pointer to a structure scale  A scaling for the outer product ...  A variable argument list of vector components Returns: GAN_TRUE on success, GAN_FALSE on failure. Increments an accumulated outer product matrix stored inside the sme structure with the outer product of a vector passed into the function in a variable argument list. The outer product is scaled by the given scaling factor scale before the matrix is incremented (equivalent to scaling the vector by the square-root of scale). See also: gan_symeigen_alloc().

Gan_Bool gan_symeigen_reset (  Gan_SymMatEigenStruct *    sme, long    size )

Initialises an accumulated outer product matrix to zero. Parameters: sme  A pointer to a structure size  The size of the matrix Returns: GAN_TRUE on success, GAN_FALSE on failure. Initialises an accumulated outer product matrix to zero. The size of the matrix is also set. See also: gan_symeigen_alloc().

Gan_Bool gan_symeigen_solve (  Gan_SymMatEigenStruct *    sme )

Eigendecomposes a matrix accumulated by summing outer products. Parameters: sme  A pointer to a structure Returns: GAN_TRUE on success, GAN_FALSE on failure. Solves for the eigenvalues and eigenvectors of a matrix accumulated within the sme structure as a sum of vector outer products. See also: gan_symeigen_alloc(), gan_symeigen_increment().

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