CellGPU: EnergyMinimizerFIRE Class Reference

Implement energy minimization via the FIRE algorithm. More...

#include <EnergyMinimizerFIRE2D.h>

Inheritance diagram for EnergyMinimizerFIRE:

Public Member Functions
	EnergyMinimizerFIRE ()
	The basic constructor.

	EnergyMinimizerFIRE (shared_ptr< Simple2DModel > system)
	The basic constructor that feeds in a target system to minimize. More...

void	initializeParameters ()
	Sets a bunch of default parameters that do not depend on the number of degrees of freedom. More...

void	initializeFromModel ()
	Set a bunch of default initialization parameters (if the State is available to determine the size of vectors) More...

virtual void	set2DModel (shared_ptr< Simple2DModel > _model)
	set the internal State to the given model

void	setMaximumIterations (int maxIt)
	Set the maximum number of iterations before terminating (or set to -1 to ignore)

void	setForceCutoff (Dscalar fc)
	Set the force cutoff.

void	setDeltaT (Dscalar dt)
	set the initial value of deltaT

void	setAlphaStart (Dscalar as)
	set the initial value of alpha and alphaStart

void	setDeltaTMax (Dscalar tmax)
	Set the maximum deltaT.

void	setDeltaTInc (Dscalar dti)
	Set the fraction by which delta increments.

void	setDeltaTDec (Dscalar dtc)
	Set the fraction by which delta decrements.

void	setAlphaDec (Dscalar ad)
	Set the fraction by which alpha decrements.

void	setNMin (int nm)
	Set the number of consecutive steps P must be non-negative before increasing delatT.

void	velocityVerlet ()
	an interface to call either the CPU or GPU velocity Verlet algorithm More...

void	velocityVerletCPU ()
	Perform a velocity Verlet step on the CPU. More...

void	velocityVerletGPU ()
	Perform a velocity Verlet step on the GPU. More...

void	fireStep ()
	an interface to call either the CPU or GPU FIRE algorithm More...

void	fireStepCPU ()
	Perform a velocity Verlet step on the CPU. More...

void	fireStepGPU ()
	Perform a velocity Verlet step on the GPU. More...

void	minimize ()
	Minimize to either the force tolerance or the maximum number of iterations. More...

virtual void	integrateEquationsOfMotion ()
	The "intergate equatios of motion just calls minimize.

void	parallelReduce (GPUArray< Dscalar > &vec)
	Test the parallel reduction routines by passing in a known vector. More...

Dscalar	getMaxForce ()
	Return the maximum force.

int	getTimestep ()
	get the number of timesteps run

Dscalar	getTime ()
	get the current simulation time

virtual void	performUpdate ()
	performUpdate just maps to integrateEquationsOfMotion

virtual void	setReproducible (bool rep)
	Set whether the source of noise should always use the same random numbers.

void	reIndexRNG (GPUArray< curandState > &array)
	re-index the any RNGs associated with the e.o.m.

virtual void	Update (int timestep)
	The fundamental function that a controlling Simulation can call.

void	setPeriod (int _p)
	set the period

void	setPhase (int _p)
	set the phase

virtual void	spatialSorting ()
	allow for spatial sorting to be called if necessary...

virtual void	setGPU ()
	Enforce GPU-only operation. This is the default mode, so this method need not be called most of the time.

virtual void	setCPU ()
	Enforce CPU-only operation. Derived classes might have to do more work when the CPU mode is invoked.

int	getNdof ()
	Get the number of degrees of freedom of the equation of motion.

void	setNdof (int _n)
	Set the number of degrees of freedom of the equation of motion.

Public Attributes
shared_ptr< Simple2DModel >	State
	The system that can compute forces, move degrees of freedom, etc.

shared_ptr< Simple2DModel >	model
	A pointer to a Simple2DModel that the updater acts on.

Protected Member Functions
void	reIndexArray (GPUArray< int > &array)
	Re-index cell arrays after a spatial sorting has occured.

void	reIndexArray (GPUArray< Dscalar > &array)
	why use templates when you can type more?

void	reIndexArray (GPUArray< Dscalar2 > &array)
	why use templates when you can type more?

Protected Attributes
int	iterations
	The number of iterations performed.

int	maxIterations
	The maximum number of iterations allowed.

Dscalar	forceMax
	The cutoff value of the maximum force.

Dscalar	forceCutoff
	The cutoff value of the maximum force.

int	N
	The number of points, or cells, or particles.

int	NMin
	The numer of consecutive time steps the power must be positive before increasing deltaT.

int	NSinceNegativePower
	The numer of consecutive time since the power has be negative.

Dscalar	deltaT
	The internal time step size.

Dscalar	deltaTMin
	The minimum time step size.

Dscalar	deltaTMax
	The maximum time step size.

Dscalar	deltaTInc
	The fraction by which deltaT can get bigger.

Dscalar	deltaTDec
	The fraction by which deltaT can get smaller.

Dscalar	Power
	The internal value of the "power".

Dscalar	alpha
	The alpha parameter of the minimization routine.

Dscalar	alphaStart
	The initial value of the alpha parameter.

Dscalar	alphaDec
	The fraction by which alpha can decrease.

GPUArray< Dscalar2 >	force
	The GPUArray containing the force.

GPUArray< Dscalar2 >	velocity
	The GPUArray containing the velocity.

GPUArray< Dscalar2 >	displacement
	an array of displacements

GPUArray< Dscalar >	forceDotVelocity
	Utility array for computing force.velocity.

GPUArray< Dscalar >	forceDotForce
	Utility array for computing force.force.

GPUArray< Dscalar >	velocityDotVelocity
	Utility array for computing velocity.velocity.

GPUArray< Dscalar >	sumReductionIntermediate
	Utility array for simple reductions.

GPUArray< Dscalar >	sumReductions
	Utility array for simple reductions.

int	Timestep
	Count the number of integration timesteps.

GPUArray< Dscalar2 >	displacements
	an internal GPUArray for holding displacements

noiseSource	noise
	A source of noise for the equation of motion.

int	Period
	The period of the updater... the updater will work every Period timesteps.

int	Phase
	The phase of the updater... the updater will work every Period timesteps offset by a phase.

bool	GPUcompute
	whether the updater does its work on the GPU or not

int	Ndof
	The number of degrees of freedom the equations of motion need to know about.

vector< int >	reIndexing
	a vector of the re-indexing information

Detailed Description

Implement energy minimization via the FIRE algorithm.

This class uses the "FIRE" algorithm to perform an energy minimization. The class is in the same framework as the simpleEquationOfMotion class, so it is called by calling performTimestep on a Simulation object that has been given the FIRE minimizer and the configuration to minimize. Each timestep, though, is a complete minimization (i.e. will run for the maximum number of iterations, or until a target tolerance has been acheived, or whatever stopping condition the user sets.