MDE solver for one direction of one block. More...

#include <Propagator.h>

Inheritance diagram for Pscf::Rp::Propagator< D, T >:

Public Types
using	PropagatorTmplT = PropagatorTmpl<typename T::Propagator>
	Direct (parent) base class.

Public Member Functions
void	setBlock (typename T::Block &block)
	Associate this propagator with a block.
virtual void	allocate (int ns, const Mesh< D > &mesh)
	Allocate memory used by this propagator.
virtual void	reallocate (int ns)
	Reallocate memory used by this propagator.
void	solve ()
	Solve the modified diffusion equation (MDE) for this block.
void	solve (typename T::RField const &head)
	Solve the MDE for a specified initial condition.
void	computeQ (double &Q) const
	Compute and return partition function for the polymer molecule.
const T::RField &	q (int i) const
	Return q-field at a specified step.
const T::RField &	head () const
	Return q-field at the initial (head) vertex.
const T::RField &	tail () const
	Return q-field at the terminal (tail) vertex.
T::Block const &	block () const
	Get the associated Block object by const reference.
Mesh< D > const &	mesh () const
	Return the associated Mesh object by const reference.
int	ns () const
	Get the number of values of s (or slices), including head and tail.
bool	isAllocated () const
	Has memory been allocated for this propagator?
const typename T::Propagator &	source (int id) const
	Get a source propagator.
const typename T::Propagator &	partner () const
	Get partner propagator.
Public Member Functions inherited from Pscf::PropagatorTmpl< T::Propagator >
void	setDirectionId (int directionId)
	Associate this propagator with a direction index.
void	setPartner (const T::Propagator &partner)
	Set the partner of this propagator.
void	addSource (const T::Propagator &source)
	Add a propagator to the list of sources for this one.
void	setIsSolved (bool isSolved)
	Set the isSolved flag to true or false.
void	setEndFlags (bool isHeadEnd, bool isTailEnd)
	Set flags indicating whether vertices are chain ends.
const T::Propagator &	source (int id) const
	Get a source propagator.
const T::Propagator &	partner () const
	Get partner propagator.
int	directionId () const
	Get direction index for this propagator.
int	nSource () const
	Number of source / prerequisite propagators.
bool	hasPartner () const
	Does this have a partner propagator?
bool	isHeadEnd () const
	Is the head vertex a chain end?
bool	isTailEnd () const
	Is the tail vertex a chain end?
bool	isSolved () const
	Has the modified diffusion equation been solved?
bool	isReady () const
	Are all source propagators solved?

Protected Member Functions
	Propagator ()
	Constructor.
	~Propagator ()
	Destructor.
void	computeHead ()
	Compute initial q-field at the head vertex.
void	solveMde ()
	Compute solution of modified diffusion equation (MDE).
T::Block &	block ()
	Get the associated Block object by non-const reference.
Protected Member Functions inherited from Pscf::PropagatorTmpl< T::Propagator >
	PropagatorTmpl ()
	Constructor.

Protected Attributes
DArray< typename T::RField >	qFields_
	Array of propagator slices at different contour variable values.
int	ns_
	Number of slices, including head and tail slices.
bool	isAllocated_
	Is this propagator allocated?

Detailed Description

template<int D, class T>
class Pscf::Rp::Propagator< D, T >

MDE solver for one direction of one block.

A fully initialized Propagator has associations with a parent Block object that owns this propagator, and with a partner Propagator that solves the MDE within the same block in the opposite direction. It also has an association with a Mesh<D> that describes a spatial grid, and associations with zero or more source Propagator objects that are used to compute an initial condition for this propagator at its head vertex.

The parent Block stores information required to numerically solve the modified diffusion equation (MDE), including quantities that depend upon the w-field associated with this block, the unit cell parameters and (in the thread model) the contour step size. These quantities are set and stored by the block because their values are the same for the two propagators owned by each block, but may be different for different blocks. The algorithm used by a Propagator to solve the MDE repeatedly calls step functions provided by the parent Block.

Specializations of this class template are used as base classes for two closely analogous class templates, also named Propagator, that are defined in the Rpc and Rpg program-level name spaces for use in the pscf_rpc and pscf_rpg programs, respectively.

Template parameters :

D dimension of space
T class with aliases for use in a program-level namespace.

Definition at line 59 of file rp/solvers/Propagator.h.

Member Typedef Documentation

◆ PropagatorTmplT

template<int D, class T>

using Pscf::Rp::Propagator< D, T >::PropagatorTmplT = PropagatorTmpl<typename T::Propagator>

Direct (parent) base class.

Definition at line 182 of file rp/solvers/Propagator.h.

Constructor & Destructor Documentation

◆ Propagator()

template<int D, class T>

Pscf::Rp::Propagator< D, T >::Propagator ( )

protected

Constructor.

Definition at line 23 of file rp/solvers/Propagator.tpp.

References isAllocated_, and ns_.

◆ ~Propagator()

template<int D, class T>

Pscf::Rp::Propagator< D, T >::~Propagator ( )

protected

Destructor.

Definition at line 34 of file rp/solvers/Propagator.tpp.

Member Function Documentation

◆ setBlock()

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::setBlock ( typename T::Block & block )

inline

Associate this propagator with a block.

Parameters

block associated Block object

Definition at line 323 of file rp/solvers/Propagator.h.

References block().

◆ allocate()

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::allocate	(	int	ns,
		const Mesh< D > &	mesh )

virtual

Allocate memory used by this propagator.

The parameter ns is the number of values of s at which q(r,s) is calculated, including the end values at the terminating vertices. See docs for the function ns(), which returns this value.

The address of the associated Mesh<D> object is retained.

An Exception is thrown if the propagator is already allocated.

Parameters

ns	number of slices (including end points at vertices)
mesh	spatial discretization mesh

Reimplemented in Pscf::Rpc::Propagator< D >, and Pscf::Rpg::Propagator< D >.

Definition at line 41 of file rp/solvers/Propagator.tpp.

References isAllocated_, mesh(), ns(), ns_, and UTIL_CHECK.

◆ reallocate()

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::reallocate ( int ns )

virtual

Reallocate memory used by this propagator.

This function is used when the value of ns is changed, which can occur during some parameter sweeps. See docs for allocate and ns.

An Exception is thrown if the propagator has not been previously allocated, or if it is allocated but the value of ns is unchanged.

Parameters

ns	number of slices (including end points)

Reimplemented in Pscf::Rpc::Propagator< D >, and Pscf::Rpg::Propagator< D >.

Definition at line 52 of file rp/solvers/Propagator.tpp.

References isAllocated_, ns(), ns_, and UTIL_CHECK.

◆ solve() [1/2]

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::solve ( )

Solve the modified diffusion equation (MDE) for this block.

This function computes an initial q-field at the head of this block, and then solves the modified diffusion equation (MDE) to propagate the solution from the head to the tail. Algorithms for the thread or bead model may be used, depending on the value of PolymerModel::model().

Definition at line 96 of file rp/solvers/Propagator.tpp.

References computeHead(), and solveMde().

◆ solve() [2/2]

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::solve ( typename T::RField const & head )

Solve the MDE for a specified initial condition.

This function solves the modified diffusion equation (MDE) for this block with a specified initial condition, which is given by the function parameter "head".

Parameters

head	initial condition of q-field at head of block

Definition at line 106 of file rp/solvers/Propagator.tpp.

References Pscf::VecOp::eqV(), head(), mesh(), qFields_, solveMde(), and UTIL_CHECK.

◆ computeQ()

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::computeQ ( double & Q ) const

Compute and return partition function for the polymer molecule.

This function computes the partition function Q for the molecule as a spatial average of the pointwise product of the initial/head slice for this propagator and the final/tail slice of its partner.

Parameters

Q	output value, spatial average of q*q^{+} at head

Definition at line 171 of file rp/solvers/Propagator.tpp.

References Pscf::PropagatorTmpl< typename T::Propagator >::hasPartner(), head(), Pscf::Reduce::innerProduct(), isAllocated_, Pscf::PolymerModel::isBead(), Pscf::PropagatorTmpl< typename T::Propagator >::isHeadEnd(), Pscf::PropagatorTmpl< T::Propagator >::isSolved(), Pscf::PropagatorTmpl< typename T::Propagator >::isSolved(), Pscf::PropagatorTmpl< T::Propagator >::isTailEnd(), mesh(), ns_, partner(), q(), Pscf::Reduce::sum(), tail(), UTIL_CHECK, and UTIL_THROW.

◆ q()

template<int D, class T>

T::RField const & Pscf::Rp::Propagator< D, T >::q ( int i ) const

inline

Return q-field at a specified step.

Parameters

i	step index, 0 <= i < ns

Definition at line 269 of file rp/solvers/Propagator.h.

References Pscf::PropagatorTmpl< typename T::Propagator >::isSolved(), qFields_, and UTIL_CHECK.

Referenced by Pscf::Rpc::Block< D >::computeConcentrationBead(), Pscf::Rpg::Block< D >::computeConcentrationBead(), Pscf::Rpc::Block< D >::computeConcentrationThread(), Pscf::Rpg::Block< D >::computeConcentrationThread(), computeQ(), Pscf::Rpc::Block< D >::computeStressBead(), Pscf::Rpg::Block< D >::computeStressBead(), Pscf::Rpc::Block< D >::computeStressThread(), and Pscf::Rpg::Block< D >::computeStressThread().

◆ head()

template<int D, class T>

T::RField const & Pscf::Rp::Propagator< D, T >::head ( ) const

inline

Return q-field at the initial (head) vertex.

Definition at line 248 of file rp/solvers/Propagator.h.

References Pscf::PropagatorTmpl< typename T::Propagator >::isSolved(), qFields_, and UTIL_CHECK.

Referenced by computeQ(), and solve().

◆ tail()

template<int D, class T>

T::RField const & Pscf::Rp::Propagator< D, T >::tail ( ) const

inline

Return q-field at the terminal (tail) vertex.

This function throws an Exception if invoked while the bead model is in use (i.e., if PolymerModel::isThread() == false) and the tail for this propagator is a chain end (i.e., if isTailEnd() == true). In this case, the tail slice is not needed, and so is not computed.

Definition at line 258 of file rp/solvers/Propagator.h.

References Pscf::PropagatorTmpl< typename T::Propagator >::isSolved(), Pscf::PropagatorTmpl< typename T::Propagator >::isTailEnd(), Pscf::PolymerModel::isThread(), ns_, qFields_, and UTIL_CHECK.

Referenced by computeHead(), and computeQ().

◆ block() [1/2]

template<int D, class T>

T::Block const & Pscf::Rp::Propagator< D, T >::block ( ) const

inline

Get the associated Block object by const reference.

Definition at line 279 of file rp/solvers/Propagator.h.

References UTIL_ASSERT.

Referenced by setBlock(), and solveMde().

◆ mesh()

template<int D, class T>

Mesh< D > const & Pscf::Rp::Propagator< D, T >::mesh ( ) const

inline

Return the associated Mesh object by const reference.

Definition at line 299 of file rp/solvers/Propagator.h.

References UTIL_ASSERT.

Referenced by allocate(), computeQ(), and solve().

◆ ns()

template<int D, class T>

int Pscf::Rp::Propagator< D, T >::ns ( ) const

inline

Get the number of values of s (or slices), including head and tail.

The value of ns is the number of values of s at which q(r,s) is calculated, including the end values at the terminating vertices (the head and tail). In the bead model, this is two more than the number of beads in the block. In the thread model, this is one more than the number length/ds of contour length steps.

Definition at line 309 of file rp/solvers/Propagator.h.

References ns_.

Referenced by allocate(), computeHead(), and reallocate().

◆ isAllocated()

template<int D, class T>

bool Pscf::Rp::Propagator< D, T >::isAllocated ( ) const

inline

Has memory been allocated for this propagator?

Definition at line 316 of file rp/solvers/Propagator.h.

References isAllocated_.

Referenced by Pscf::Rpc::Block< D >::computeStressThread(), and solveMde().

◆ computeHead()

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::computeHead ( )

protected

Compute initial q-field at the head vertex.

In either the thread or bead model, the head slice of each propagator is the product of tail slices for incoming propagators from other bonds that terminate at the head vertex, or 1 for a chain end.

Definition at line 64 of file rp/solvers/Propagator.tpp.

References Pscf::VecOp::eqS(), isAllocated_, Pscf::PropagatorTmpl< typename T::Propagator >::isHeadEnd(), Pscf::PropagatorTmpl< T::Propagator >::isSolved(), Pscf::VecOp::mulEqV(), ns(), Pscf::PropagatorTmpl< typename T::Propagator >::nSource(), qFields_, source(), tail(), UTIL_CHECK, and UTIL_THROW.

Referenced by solve().

◆ solveMde()

template<int D, class T>

void Pscf::Rp::Propagator< D, T >::solveMde ( )

protected

Compute solution of modified diffusion equation (MDE).

This function accesses a precomputed head slice qFields_[0] and computes the rest of the propagator.

Definition at line 121 of file rp/solvers/Propagator.tpp.

References block(), Pscf::VecOp::eqV(), isAllocated(), Pscf::PolymerModel::isBead(), Pscf::PropagatorTmpl< typename T::Propagator >::isHeadEnd(), Pscf::PropagatorTmpl< typename T::Propagator >::isTailEnd(), Pscf::PolymerModel::isThread(), ns_, qFields_, Pscf::PropagatorTmpl< typename T::Propagator >::setIsSolved(), UTIL_CHECK, and UTIL_THROW.

Referenced by solve(), and solve().

◆ block() [2/2]

template<int D, class T>

T::Block & Pscf::Rp::Propagator< D, T >::block ( )

inlineprotected

Get the associated Block object by non-const reference.

Definition at line 289 of file rp/solvers/Propagator.h.

References UTIL_ASSERT.

◆ source()

template<int D, class T>

const typename T::Propagator & Pscf::PropagatorTmpl< typename T::Propagator >::source ( int id ) const

Get a source propagator.

Parameters

id	index of source propagator, < nSource

Referenced by computeHead().

◆ partner()

template<int D, class T>

const typename T::Propagator & Pscf::PropagatorTmpl< typename T::Propagator >::partner ( ) const

Get partner propagator.

Referenced by computeQ().

Member Data Documentation

◆ qFields_

template<int D, class T>

DArray<typename T::RField> Pscf::Rp::Propagator< D, T >::qFields_

protected

Array of propagator slices at different contour variable values.

Definition at line 191 of file rp/solvers/Propagator.h.

Referenced by computeHead(), head(), q(), solve(), solveMde(), and tail().

◆ ns_

template<int D, class T>

int Pscf::Rp::Propagator< D, T >::ns_

protected

Number of slices, including head and tail slices.

Definition at line 194 of file rp/solvers/Propagator.h.

Referenced by allocate(), computeQ(), ns(), Propagator(), reallocate(), solveMde(), and tail().

◆ isAllocated_

template<int D, class T>

bool Pscf::Rp::Propagator< D, T >::isAllocated_

protected

Is this propagator allocated?

Definition at line 197 of file rp/solvers/Propagator.h.

Referenced by allocate(), computeHead(), computeQ(), isAllocated(), Propagator(), and reallocate().

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

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ PropagatorTmplT

Constructor & Destructor Documentation

◆ Propagator()

◆ ~Propagator()

Member Function Documentation

◆ setBlock()

◆ allocate()

◆ reallocate()

◆ solve() [1/2]

◆ solve() [2/2]

◆ computeQ()

◆ q()

◆ head()

◆ tail()

◆ block() [1/2]

◆ mesh()

◆ ns()

◆ isAllocated()

◆ computeHead()

◆ solveMde()

◆ block() [2/2]

◆ source()

◆ partner()

Member Data Documentation

◆ qFields_

◆ ns_

◆ isAllocated_