diff --git a/doc/handbook/4_restartsimulations.tex b/doc/handbook/4_restartsimulations.tex index 30ce43199130c08f732e92fc3fff16ff43d8272e..fbd12fe9f9804268b218c330928e3aa5fa66c66a 100644 --- a/doc/handbook/4_restartsimulations.tex +++ b/doc/handbook/4_restartsimulations.tex @@ -1,26 +1,19 @@ \section{Restart \Dumux Simulations} \label{sc_restartsimulations} -Restart is currently not available in the \DumuxVersion~release. We are working on it! -% You can restart the simulation -% from a specific point in time or extend the simulation beyond the originally -% end of simulation. What you need is a \texttt{*.drs} file (which contains the -% all necessary restart information. -% Then you can simply restart a simulation via -% \begin{lstlisting}[style=Bash] -% ./test_program -TimeManager.Restart RESTART_TIME -% \end{lstlisting} -% To test restart behavior, use the \texttt{test\_box1p2cni} problem -% in the \texttt{test/implicit/1p2c} folder. -% You get the \texttt{RESTART\_TIME} from the name of your \texttt{.drs} file. -% Restarting will only work when the exact time from an existing restart file is given. -% If you need more restart files, you can change the frequency -% by including the function into your problem: -% \begin{lstlisting}[style=DumuxCode] -% // Writes a restart file every 5th time step -% bool shouldWriteRestartFile() const -% { -% return (this->timeManager().timeStepIndex() % 5 == 0); -% } -% \end{lstlisting} +\Dumux has some experimental support for check-pointing (restarting paused/stopped/crashed simulations). +You can restart a \Dumux simulation from any time point where a VTK file was written out. +This is currently only supported for sequential, non-adaptive simulations. For adaptive simulation +the full hierarchical grid has to be stored. This is usually done with the grid's \texttt{BackupRestoreFacility}. +There is currently no special support by \Dumux for that, but it is possible to implement +a restart using \texttt{BackupRestoreFacility} with plain Dune. +For VTK files the output can be read with the free function \texttt{loadSolution}. Grids can be read with +the \texttt{Dumux::VTKReader} or you can simply recreate the grid as you did in the first simulation run. + +Unfortunately, writing double-precision floating point numbers to VTK files is only available with Dune master (will be in 2.7). +That's why we currently only support single precision restart, meaning some information will be lost if you are computing +in double precision. + +The restart capabilities will hopefully be improved in future versions of \Dumux 3. +We are happy about any contributions (especially HDF5 / XDMF support, improvement of VTK support).