petsc-3.8.4 2018-03-24

TSSetSolutionFunction

Provide a function that computes the solution of the ODE or DAE

Synopsis

#include "petscts.h"  
PetscErrorCode  TSSetSolutionFunction(TS ts,PetscErrorCode (*f)(TS,PetscReal,Vec,void*),void *ctx)

Logically Collective on TS

Input Parameters

	ts	- the TS context obtained from TSCreate()
	f	- routine for evaluating the solution
	ctx	- [optional] user-defined context for private data for the function evaluation routine (may be NULL)

Calling sequence of func

    func (TS ts,PetscReal t,Vec u,void *ctx);

	t	- current timestep
	u	- output vector
	ctx	- [optional] user-defined function context

Notes

This routine is used for testing accuracy of time integration schemes when you already know the solution. If analytic solutions are not known for your system, consider using the Method of Manufactured Solutions to create closed-form solutions with non-physical forcing terms.

For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.

Keywords