A container into which any other c2_function can be dropped.It allows a function to be pre-evaluated at a point, and used at multiple places in an expression efficiently. If it is re-evaluated at the previous point, it returns the remembered values; otherwise, it re-evauates the function at the new point. More...

#include <c2_function.hh>

Inheritance diagram for c2_cached_function_p< float_type >:

Public Member Functions
	c2_cached_function_p (const c2_function< float_type > &f)
	construct the container More...

virtual float_type	value_with_derivatives (float_type x, float_type yprime, float_type yprime2) const throw (c2_exception)
	get the value and derivatives. More...

Public Member Functions inherited from c2_function< float_type >
const std::string	cvs_header_vers () const
	get versioning information for the header file More...

const std::string	cvs_file_vers () const
	get versioning information for the source file More...

virtual	~c2_function ()
	destructor More...

float_type	operator() (float_type x) const throw (c2_exception)
	evaluate the function in the classic way, ignoring derivatives. More...

float_type	operator() (float_type x, float_type yprime, float_type yprime2) const throw (c2_exception)
	get the value and derivatives. More...

float_type	find_root (float_type lower_bracket, float_type upper_bracket, float_type start, float_type value, int error=0, float_type final_yprime=0, float_type *final_yprime2=0) const throw (c2_exception)
	solve f(x)==value very efficiently, with explicit knowledge of derivatives of the function More...

float_type	partial_integrals (std::vector< float_type > xgrid, std::vector< float_type > *partials=0, float_type abs_tol=1e-12, float_type rel_tol=1e-12, int derivs=2, bool adapt=true, bool extrapolate=true) const throw (c2_exception)
	for points in xgrid, adaptively return Integral[f(x),{x,xgrid[i],xgrid[i+1]}] and return in vector, along with sum More...

float_type	integral (float_type amin, float_type amax, std::vector< float_type > *partials=0, float_type abs_tol=1e-12, float_type rel_tol=1e-12, int derivs=2, bool adapt=true, bool extrapolate=true) const throw (c2_exception)
	a fully-automated integrator which uses the information provided by the get_sampling_grid() function to figure out what to do. More...

c2_piecewise_function_p < float_type > *	adaptively_sample (float_type amin, float_type amax, float_type abs_tol=1e-12, float_type rel_tol=1e-12, int derivs=2, std::vector< float_type > xvals=0, std::vector< float_type > yvals=0) const throw (c2_exception)
	create a c2_piecewise_function_p from c2_connector_function_p segments which is a representation of the parent function to the specified accuracy, but maybe much cheaper to evaluate More...

float_type	xmin () const
	return the lower bound of the domain for this function as set by set_domain() More...

float_type	xmax () const
	return the upper bound of the domain for this function as set by set_domain() More...

void	set_domain (float_type amin, float_type amax)
	set the domain for this function. More...

size_t	get_evaluations () const
	this is a counter owned by the function but which can be used to monitor efficiency of algorithms. More...

void	reset_evaluations () const
	reset the counter More...

void	increment_evaluations () const
	count evaluations More...

bool	check_monotonicity (const std::vector< float_type > &data, const char message[]) const throw (c2_exception)
	check that a vector is monotonic, throw an exception if not, and return a flag if it is reversed More...

virtual void	set_sampling_grid (const std::vector< float_type > &grid) throw (c2_exception)
	establish a grid of 'interesting' points on the function. More...

std::vector< float_type > *	get_sampling_grid_pointer () const
	get the sampling grid, which may be a null pointer More...

virtual void	get_sampling_grid (float_type amin, float_type amax, std::vector< float_type > &grid) const
	return the grid of 'interesting' points along this function which lie in the region requested More...

void	preen_sampling_grid (std::vector< float_type > *result) const
	clean up endpoints on a grid of points More...

void	refine_sampling_grid (std::vector< float_type > &grid, size_t refinement) const
	refine a grid by splitting each interval into more intervals More...

c2_function< float_type > &	normalized_function (float_type amin, float_type amax, float_type norm=1.0) const throw (c2_exception)
	create a new c2_function from this one which is normalized on the interval More...

c2_function< float_type > &	square_normalized_function (float_type amin, float_type amax, float_type norm=1.0) const throw (c2_exception)
	create a new c2_function from this one which is square-normalized on the interval More...

c2_function< float_type > &	square_normalized_function (float_type amin, float_type amax, const c2_function< float_type > &weight, float_type norm=1.0) const throw (c2_exception)
	create a new c2_function from this one which is square-normalized with the provided weight on the interval More...

c2_sum_p< float_type > &	operator+ (const c2_function< float_type > &rhs) const
	factory function to create a c2_sum_p from a regular algebraic expression. More...

c2_diff_p< float_type > &	operator- (const c2_function< float_type > &rhs) const
	factory function to create a c2_diff_p from a regular algebraic expression. More...

c2_product_p< float_type > &	operator* (const c2_function< float_type > &rhs) const
	factory function to create a c2_product_p from a regular algebraic expression. More...

c2_ratio_p< float_type > &	operator/ (const c2_function< float_type > &rhs) const
	factory function to create a c2_ratio_p from a regular algebraic expression. More...

c2_composed_function_p < float_type > &	operator() (const c2_function< float_type > &inner) const
	compose this function outside another. More...

float_type	get_trouble_point () const
	Find out where a calculation ran into trouble, if it got a nan. If the most recent computation did not return a nan, this is undefined. More...

void	claim_ownership () const
	increment our reference count. Destruction is only legal if the count is zero. More...

size_t	release_ownership_for_return () const throw (c2_exception)
	decrement our reference count. Do not destroy at zero. More...

void	release_ownership () const throw (c2_exception)
	decrement our reference count. If the count reaches zero, destroy ourself. More...

size_t	count_owners () const
	get the reference count, mostly for debugging More...

void	fill_fblock (c2_fblock< float_type > &fb) const throw (c2_exception)
	fill in a c2_fblock<float_type>... a shortcut for the integrator & sampler More...

Protected Member Functions
	c2_cached_function_p ()

Protected Member Functions inherited from c2_function< float_type >
	c2_function (const c2_function< float_type > &src)

	c2_function ()

virtual void	set_sampling_grid_pointer (std::vector< float_type > &grid)

Protected Attributes
const c2_const_ptr< float_type >	func

bool	init

float_type	x0

float_type	y

float_type	yp

float_type	ypp

Protected Attributes inherited from c2_function< float_type >
std::vector< float_type > *	sampling_grid

bool	no_overwrite_grid

float_type	fXMin

float_type	fXMax

size_t	evaluations

float_type	bad_x_point
	this point may be used to record where a calculation ran into trouble More...

Detailed Description

template<typename float_type = double>
class c2_cached_function_p< float_type >

A container into which any other c2_function can be dropped.

It allows a function to be pre-evaluated at a point, and used at multiple places in an expression efficiently. If it is re-evaluated at the previous point, it returns the remembered values; otherwise, it re-evauates the function at the new point.

The factory function c2_factory::cached_function() creates *new c2_cached_function_p

Definition at line 937 of file c2_function.hh.

Constructor & Destructor Documentation

template<typename float_type = double>

c2_cached_function_p< float_type >::c2_cached_function_p ( const c2_function< float_type > & f )

inline

construct the container

Parameters

f	the function to be cached

Definition at line 942 of file c2_function.hh.

942 : c2_function<float_type>(),

943 func(f), init(false) {}

c2_cached_function_p::func

const c2_const_ptr< float_type > func

Definition: c2_function.hh:962

c2_function

the parent class for all c2_functions.c2_functions know their value, first, and second derivative at ...

Definition: c2_function.hh:138

c2_cached_function_p::init

bool init

Definition: c2_function.hh:963

template<typename float_type = double>

c2_cached_function_p< float_type >::c2_cached_function_p ( )

inlineprotected

Definition at line 961 of file c2_function.hh.

961 : func() {} // hide default constructor, since its use is almost always an error.

c2_cached_function_p::func

const c2_const_ptr< float_type > func

Definition: c2_function.hh:962

Member Function Documentation

template<typename float_type = double>

virtual float_type c2_cached_function_p< float_type >::value_with_derivatives	(	float_type	x,
		float_type *	yprime,
		float_type *	yprime2
	)		const
throw	(	c2_exception
	)

inlinevirtual

get the value and derivatives.

There is required checking for null pointers on the derivatives, and most implementations should operate faster if derivatives are not needed.

Parameters

[in]	x	the point at which to evaluate the function
[out]	yprime	the first derivative (if pointer is non-null)
[out]	yprime2	the second derivative (if pointer is non-null)

Returns: the value of the function

Checks to see if the function is being re-evaluated at the previous point, and returns remembered values if so.

Implements c2_function< float_type >.

Definition at line 948 of file c2_function.hh.

References c2_cached_function_p< float_type >::func, c2_cached_function_p< float_type >::init, test::x, c2_cached_function_p< float_type >::x0, c2_cached_function_p< float_type >::y, c2_cached_function_p< float_type >::yp, and c2_cached_function_p< float_type >::ypp.

     {
                 if(!init || x != x0) {
                         y=this->func->value_with_derivatives(x, &yp, &ypp);
                         x0=x;
                         init=true;
                 }
                 if(yprime) *yprime=yp;
                 if(yprime2) *yprime2=ypp;
                 return y; 
         }