Newton iterator for multi-domain, one-dimensional problems. More...

#include <MultiNewton.h>

Public Member Functions
	MultiNewton (int sz)

size_t	size ()

void	step (doublereal x, doublereal step, OneDim &r, MultiJac &jac, int loglevel)
	Compute the undamped Newton step. More...

doublereal	boundStep (const doublereal x0, const doublereal step0, const OneDim &r, int loglevel)
	Return the factor by which the undamped Newton step 'step0' must be multiplied in order to keep all solution components in all domains between their specified lower and upper bounds. More...

int	dampStep (const doublereal x0, const doublereal step0, doublereal x1, doublereal step1, doublereal &s1, OneDim &r, MultiJac &jac, int loglevel, bool writetitle)
	On entry, step0 must contain an undamped Newton step for the solution x0. More...

doublereal	norm2 (const doublereal x, const doublereal step, OneDim &r) const
	Compute the weighted 2-norm of `step`. More...

int	solve (doublereal x0, doublereal x1, OneDim &r, MultiJac &jac, int loglevel)
	Find the solution to F(X) = 0 by damped Newton iteration. More...

void	setOptions (int maxJacAge=5)
	Set options. More...

void	resize (size_t points)
	Change the problem size. More...

Protected Attributes
vector_fp	m_x
	Work arrays of size m_n used in solve(). More...

vector_fp	m_stp

vector_fp	m_stp1

int	m_maxAge

size_t	m_n
	number of variables More...

doublereal	m_elapsed

Detailed Description

Newton iterator for multi-domain, one-dimensional problems.

Used by class OneDim.

Definition at line 19 of file MultiNewton.h.

Member Function Documentation

◆ step()

void step	(	doublereal *	x,
		doublereal *	step,
		OneDim &	r,
		MultiJac &	jac,
		int	loglevel
	)

Compute the undamped Newton step.

The residual function is evaluated at x, but the Jacobian is not recomputed.

Definition at line 162 of file MultiNewton.cpp.

References Domain1D::componentName(), OneDim::domain(), OneDim::eval(), BandMatrix::info(), Domain1D::nComponents(), OneDim::nDomains(), Cantera::npos, OneDim::size(), BandMatrix::solve(), and OneDim::start().

Referenced by MultiNewton::norm2(), and MultiNewton::solve().

◆ boundStep()

doublereal boundStep	(	const doublereal *	x0,
		const doublereal *	step0,
		const OneDim &	r,
		int	loglevel
	)

Return the factor by which the undamped Newton step 'step0' must be multiplied in order to keep all solution components in all domains between their specified lower and upper bounds.

Definition at line 196 of file MultiNewton.cpp.

References OneDim::domain(), OneDim::nDomains(), and OneDim::start().

◆ dampStep()

int dampStep	(	const doublereal *	x0,
		const doublereal *	step0,
		doublereal *	x1,
		doublereal *	step1,
		doublereal &	s1,
		OneDim &	r,
		MultiJac &	jac,
		int	loglevel,
		bool	writetitle
	)

On entry, step0 must contain an undamped Newton step for the solution x0.

This method attempts to find a damping coefficient such that the next undamped step would have a norm smaller than that of step0. If successful, the new solution after taking the damped step is returned in x1, and the undamped step at x1 is returned in step1.

Definition at line 208 of file MultiNewton.cpp.

References Cantera::writelog().

Referenced by MultiNewton::solve().