From 852ef9dcdf1e40d9b04fc4fa0a2f3ef40adfb687 Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Fri, 28 Jun 2024 16:15:19 -0600 Subject: [PATCH] Link to step-86 from other parts of the library. --- examples/step-26/doc/results.dox | 15 +++++++++------ include/deal.II/base/parsed_function.h | 4 ++-- include/deal.II/lac/petsc_ts.h | 3 ++- 3 files changed, 13 insertions(+), 9 deletions(-) diff --git a/examples/step-26/doc/results.dox b/examples/step-26/doc/results.dox index 0f78c6d8e9..36cf16c28c 100644 --- a/examples/step-26/doc/results.dox +++ b/examples/step-26/doc/results.dox @@ -86,8 +86,8 @@ Ralf Hartmann, published by the University of Heidelberg, Germany, in 2002 We here use one of the simpler time stepping methods, namely the second order in time Crank-Nicolson method. This is surely already better than the even -more widely used (and even less accurate) implicit Euler method, -but many other, more accurate methods such as +more widely used (and even less accurate) implicit (=backward) Euler method, +but many other, more accurate methods such as BDF or Runge-Kutta methods are available and should be used as they do not represent much additional effort. It is not difficult to implement this for the current program, if one wanted; a more systematic treatment is also given in step-52. @@ -100,12 +100,15 @@ this category, and "standard" time stepping methods are all we need here.) Rather, one should use one of the available high-quality libraries for time stepping, for the same reasons as one should not be implementing finite element methods by hand but use deal.II instead. -Indeed, deal.II has interfaces to one such time stepping library, -[SUNDIALS](https://computing.llnl.gov/projects/sundials), already available. +Indeed, deal.II has interfaces to two such time stepping library, +[SUNDIALS](https://computing.llnl.gov/projects/sundials) and the +[PETSc TS package](https://petsc.org/release/manualpages/TS/TS/), already available. In particular, the SUNDIALS::ARKode class would make for a great starting -point for the use of much better (and much more accurate) time steppers; +point for the use of much better (and much more accurate) time steppers, +as would PETScWrappers::TimeStepper; the methods one would then get also implement the automatic time step -control mentioned above. +control mentioned above. To see how this works, take a look at +step-86.

Better refinement criteria

diff --git a/include/deal.II/base/parsed_function.h b/include/deal.II/base/parsed_function.h index 142e23c92e..a8b2372636 100644 --- a/include/deal.II/base/parsed_function.h +++ b/include/deal.II/base/parsed_function.h @@ -31,8 +31,8 @@ namespace Functions { /** * Friendly interface to the FunctionParser class. This class is meant as a - * wrapper for the FunctionParser class. It is used in the step-34 tutorial - * program. + * wrapper for the FunctionParser class. It is used in the step-34 and step-86 + * tutorial programs. * * It provides two methods to declare and parse a ParameterHandler object * and creates the Function object declared in the parameter file. This diff --git a/include/deal.II/lac/petsc_ts.h b/include/deal.II/lac/petsc_ts.h index 8d00f93bbb..e07857492c 100644 --- a/include/deal.II/lac/petsc_ts.h +++ b/include/deal.II/lac/petsc_ts.h @@ -210,7 +210,8 @@ namespace PETScWrappers /** * Interface to the PETSc TS solver for Ordinary Differential Equations * and Differential-Algebraic Equations. The TS solver is described in the - * [PETSc manual](https://petsc.org/release/manual/ts/). + * [PETSc manual](https://petsc.org/release/manual/ts/). This class is used + * and extensively discussed in step-86. * * This class supports two kinds of formulations. * The explicit formulation: -- 2.39.5