psi::extrema::math_tools Class Reference

A general mathematics routine class. More...

#include <math_tools.h>

Inheritance diagram for psi::extrema::math_tools:

List of all members.

Protected Member Functions
	math_tools ()
	Default constructor, does nothing.
	~math_tools ()
	Default destructor, does nothing.
double *	newton_step (int dim, double **_Hi, double *g)
	Computes the Newton-Raphson optimization step.
double **	update_bfgs (int dim, double *_var_dif, double *grad_dif, double **_Hi_old)
	Performs bfgs update on inverse of hessian matrix.
double **	update_ms (int dim, double *_var_dif, double *_grad_dif, double **_Hi_old)
	Performs update on inverse of hessian matrix attributed to Murtah and Sargent among many others.
double **	rep_reduce (char *label, double **rep_matrix, int reps)
	Reduces a set of representation vectors.
double **	rep_project (char *label, int dim_vec, double **result_vecs, int *irrep_proj)
	Projects out irrep components from a reducible representation.
double **	orthogonalize (int nvecs, int dimvecs, double **vecs, int normalize, double norm_tol, int *nindep)
	Othogonalizes a set of vectors.

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Detailed Description

A general mathematics routine class.

General implementations of basic mathematical algorithms. The only dependency other than standard libraries is the PSI 3.0 library libciomr.

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Member Function Documentation

double * math_tools::newton_step	(	int	dim,
		double **	_Hi,
		double *	g
	)			[protected]

Computes the Newton-Raphson optimization step.

Parameters:

	dim	number of variables
	**_Hi	inverse hessian matrix
	*g	gradient vector

Returns:

*_s displacement vector

double ** math_tools::update_bfgs	(	int	dim,
		double *	_var_dif,
		double *	_grad_dif,
		double **	_Hi_old
	)			[protected]

Performs bfgs update on inverse of hessian matrix.

Parameters:

	dim	dimension of hessian inverse
	*_var_dif	difference of current and previous variable
	*grad_dif	difference of current and previous gradient
	**_Hi_old	inverse hessian from previous iteration

Returns:

**_Hi_new updated hessian inverse

double ** math_tools::update_ms	(	int	dim,
		double *	_var_dif,
		double *	_grad_dif,
		double **	_Hi_old
	)			[protected]

Performs update on inverse of hessian matrix attributed to Murtah and Sargent among many others.

Parameters:

	dim	dimension of hessian inverse
	*_var_dif	difference of current and previous variable
	*_grad_dif	difference of current and previous gradient
	**_Hi_old	inverse hessian from previous iteration

Returns:

**_Hi_new = updated hessian inverse

double ** math_tools::rep_reduce	(	char *	label,
		double **	rep_matrix,
		int	num_reps
	)			[protected]

Reduces a set of representation vectors.

Parameters:

	label	the point group label
	rep_matrix	the matrix of representations, each representation should be a row of this matrix whose length = number of irreps Parses input

double ** math_tools::rep_project	(	char *	label,
		int	dim_vec,
		double **	result_vecs,
		int *	irrep_proj
	)			[protected]

Projects out irrep components from a reducible representation.

Parameters:

	label	point group label
	num_vars	dimension of the vector
	vectors	resulting from each symmetry operation
	irrep_proj	1 if irrep should be projected out and returned

double ** math_tools::orthogonalize	(	int	nvecs,
		int	dimvecs,
		double **	vecs,
		int	normalize,
		double	norm_tol,
		int *	nindep
	)			[protected]

Othogonalizes a set of vectors.

Parameters:

	nvecs	number of vectors to orthogonalize
	dimvecs	length of each vector
	vec	nvec x dimvecs matrix containing vectors
	nindep	where number of independent vectors is saved
	norm_tol	norm of vectors big enough to keep
	normalize	1 if vectors should be normalized as well /*------------------------------------------------------------------------

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The documentation for this class was generated from the following files:

• math_tools.h
• math_tools.cc
• bin/extrema/Math_Tools/symmetry.cc