Diffpack Documentation

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SpaceTimeScale Class Reference

stores a physical scaling for space and time. More...

#include <SpaceTimeScale.h>

Inheritance diagram for SpaceTimeScale::

List of all members.

Public Methods
	SpaceTimeScale (int nsd)
	~SpaceTimeScale ()
void	defaultInit ()
bool	defaultScale ()
void	define (MenuSystem &menu, int level=MAIN)
void	scan (MenuSystem &menu)
void	setSpaceScale (const Ptv(real) &scale, const Ptv(real) &origin)
void	setSpaceScale (real scale)
void	setTimeScale (real scale)
void	scale (MatSimple(real) &grid_point_coordinates)
void	unscale (MatSimple(real) &grid_point_coordinates)
void	scale (VecSimple(real) &grid_point_coordinates, int dir)
void	unscale (VecSimple(real) &grid_point_coordinates, int dir)
void	scale (Ptv(real) &x, bool interval=false)
void	unscale (Ptv(real) &x, bool interval=false)
Static Public Methods
void	defineStatic (MenuSystem &menu, int level=MAIN)
Public Attributes
Ptv(real)	grid_scale_factor
Ptv(real)	grid_scale_reference
real	time_scale_factor
real	time_scale_reference

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Detailed Description

stores a physical scaling for space and time.

NAME: SpaceTimeScale - stores a physical scaling for space and time

DESCRIPTION:

The class represent a scaling of space and time to be used together with field and grid classes when solving PDEs. The user can conveniently set the scaling parameters on the menu. A "SpaceTimeScale" object is attached to grid(s) and fields prior to their use. Normally, grids and fields have handles to a single "SpaceTimeScale" object.

The scaling is described in terms of a factor and a reference value according to the formula "p=factor*(q-reference)", where "p" is the new dimensionless parameter, "q" is the physical parameter (usually with a dimension), "reference" is a reference value that is often zero and "factor" is the scaling factor (hence "1/factor" is the scale of the "q" parameter).

The "SpaceTimeScale" object contains a grid scaling (factor and reference) for each space dimension and a time scaling (factor and reference).

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Constructor & Destructor Documentation

SpaceTimeScale::SpaceTimeScale ( int nsd )

There is one constructor that takes the number of space dimensions as reference. This constructor calls "defaultInit" which sets the standard default scaling: the factor is unity and the reference is zero, that is, the scaling has no effect. Further initialization is not necessary, but non-trivial scalings can be assigned either by using the menu functions or by setting the scale parmeters directly (these are public data members).

SpaceTimeScale::~SpaceTimeScale ( )

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Member Function Documentation

void SpaceTimeScale::defaultInit ( )

sets the factor to unity and the reference to zero for both the space and time scale.

bool SpaceTimeScale::defaultScale ( )

returns true if the scale for both space and time corresponds to unity factor and zero reference (the defualt, or trivial, scale).

void SpaceTimeScale::define ( MenuSystem & menu, int level = MAIN )

standard menu functions that enable convenient settings of the scale parameters on a menu.

static void SpaceTimeScale::defineStatic ( MenuSystem & menu, int level = MAIN ) [static]

standard menu functions that enable convenient settings of the scale parameters on a menu.

void SpaceTimeScale::scale ( Ptv(real) & x, bool interval = false )

See documentation of one of the overloaded functions.

void SpaceTimeScale::scale ( VecSimple(real) & grid_point_coordinates, int dir )

See documentation of one of the overloaded functions.

void SpaceTimeScale::scale ( MatSimple(real) & grid_point_coordinates )

performs the scaling on the argument (matrix or "Ptv" object). This is a utility function that is called from grid objects. Time parameter objects (of class "TimePrm") have special built-in for manipulating the time parameters. Grids, on the other hand, often have many arrays and it is convenient to have utility functions like "scale" and "unscale" here in class "SpaceTimeScale" which can be re-used by many grid classes. The second argument "interval" in one of the overloaded "scale" functions indicates whether the argument "x" reflects an interval, contrary to a length (the reference value has no effect on interval quantities). Contrary to other objects that also have "scale" and "unscale" functions ("ScalarScale", fields, grids), there is no indicator in "SpaceTimeScale" that "scale" or "unscale" has been called. Hence, calling "scale" twice for the same argument, the scaling will also be applied twice. However, grid objects (which are the users of the "scale" and "unscale" functions here) have internal indicators ("is_scaled") such that calling a grid's "scale" function twice will only lead to one call to the real scaling in "SpaceTimeScale scale".

void SpaceTimeScale::scan ( MenuSystem & menu )

standard menu functions that enable convenient settings of the scale parameters on a menu.

void SpaceTimeScale::setSpaceScale ( real scale )

See documentation of one of the overloaded functions.

void SpaceTimeScale::setSpaceScale ( const Ptv(real) & scale, const Ptv(real) & origin )

alternative to "scan" for setting the space and time scale directly in a program.

void SpaceTimeScale::setTimeScale ( real scale )

alternative to "scan" for setting the space and time scale directly in a program.

void SpaceTimeScale::unscale ( Ptv(real) & x, bool interval = false )

See documentation of one of the overloaded functions.

void SpaceTimeScale::unscale ( VecSimple(real) & grid_point_coordinates, int dir )

See documentation of one of the overloaded functions.

void SpaceTimeScale::unscale ( MatSimple(real) & grid_point_coordinates )

performs the inverse operation of "scale".

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Member Data Documentation

Ptv(real) SpaceTimeScale::grid_scale_factor

Ptv(real) SpaceTimeScale::grid_scale_reference

real SpaceTimeScale::time_scale_factor

real SpaceTimeScale::time_scale_reference

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

• SpaceTimeScale.h

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