\newcommand{\boost}{{\specialword{Boost}}\xspace}
\newcommand{\kokkos}{{\specialword{Kokkos}}\xspace}
\newcommand{\llvm}{{\specialword{LLVM}}\xspace}
+\newcommand{\step}[1]{{\specialword{step-#1}}\xspace}
%Trilinos Packages
\newcommand{\epetra}{{\specialword{Epetra}}\xspace}
object-oriented finite element library used around the world in the
development of finite element solvers. It is available for free under the
terms of the \emph{GNU Lesser General Public License} (LGPL). The \dealii
-project is in the process of relicsensing the library under the terms of
+project is in the process of relicensing the library under the terms of
the \emph{Apache License} 2.0 with \emph{LLVM Exception}. Downloads are
available at \url{https://www.dealii.org/} and
\url{https://github.com/dealii/dealii}.
(Section~\ref{sec:tools}).
\item
There are six new tutorial programs, on checkpointing simulations
- (step-83), integrating time-dependent solvers with external time
- stepping libraries (step-86, using \petsc's \ts{} library), advanced
- point evaluation techniques (step-87), non-matching grids (step-89),
- and trace-based methods for PDEs on embedded surfaces (step-90). See
+ (\step{83}), integrating time-dependent solvers with external time
+ stepping libraries (\step{86}, using \petsc's \ts{} library), advanced
+ point evaluation techniques (\step{87}), non-matching grids (\step{89}),
+ and trace-based methods for PDEs on embedded surfaces (\step{90}). See
Section~\ref{subsec:steps} for more details.
\item
In Section~\ref{sec:license} we summarize the motivation and approach
common when using hanging node constraints (here, $x_3$ could
represent the value of the solution at a hanging node, and $x_{14}$
and $x_{15}$ are the values of the two adjacent degrees of freedom on
- the parent edge that contains the hanging node); of they can be of
+ the parent edge that contains the hanging node); or they can be of
the form $x_{12}=42$ as is common when using Dirichlet boundary
conditions.
\texttt{AffineConstraints} class interface required building such
constraints in multiple steps: First, one declared a degree of
freedom as constrained; then one added the dependencies one after
- the other (e.g., by adding pairs $(\frac 12, 13)$ and $(\frac 12,
- 14)$ in the hanging node example above); then one added
+ the other (e.g., by adding pairs $(\frac 12, 14)$ and $(\frac 12,
+ 15)$ in the hanging node example above); then one added
inhomogeneities (by setting it to $42$ in the Dirichlet example
above). This piecemeal approach is cumbersome and prevents the
library from performing certain error checking steps because a
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{Updates of multigrid and matrix-free algorithms}\label{sec:mf}
-We made different updates of the matrix-free infrastructure in \dealii. These include:
+We made different updates of the multigrid and matrix-free infrastructure in \dealii. These include:
\begin{itemize}
\item Our own implementation of \texttt{std::simd}, called
\texttt{VectorizedArray}, now also supports Arm Neon. Arm Neon is an
Interfaces are named in analogy to \texttt{FEEvaluation}, in order to seamlessly switch the
local evaluator functionality at quadrature points of a computation. The key component is the
underlying MPI communication infrastructure, which is performed via \texttt{RemotePointEvaluation}.
-Tutorial step-89 has been added to present its usage
+Tutorial \step{89} has been added to present its usage
in the context of the application to acoustic conservation equations~\cite{heinz2023high}.
\item FECouplingValues
\dealii{}'s parallel linear algebra facilities (apart from matrix-free capabilities) are largely built on
wrappers around functionality provided by the \petsc{} and \trilinos{} libraries.
-Historically, \trilinos{} has implemented distributed linear algebra-classes for vectors and (sparse) matrices in its
+Historically, \trilinos{} has implemented distributed linear algebra classes for vectors and (sparse) matrices in its
\epetra{} package that uses \MPI{} as its only source of
parallelism. Building on that, there are multiple interconnected \trilinos{} packages, e.g.\ for (non)-linear solvers
and preconditioners, commonly referred to as the
we will eventually have to switch all of our \trilinos{} interfaces to \tpetra{};
the same is true for the need to switch to \tpetra{}-based
sub-packages replacing existing \trilinos{} sub-packages
-(for example, Ifpack2 instead of Ifpack).
+(for example, \texttt{Ifpack2} instead of \texttt{Ifpack}).
In the current release, we have put substantial work into this switch,
as outlined below. As this is not yet finished, it is important to note that
\item The constructor for the class \texttt{TrilinosWrappers::MPI::Vector} only required the \texttt{IndexSet locally\_owned},
which describes the set of indices locally owned by the current rank.
However, if one wants to create a vector that has read or write access to non-locally owned indices, the constructor of the
- \texttt{TpetraWrappers::Vector} requires \texttt{IndexSet locally\_owned}, the \texttt{IndexSet locally\_relevant}, and
+ \texttt{TpetraWrappers::Vector} requires the \texttt{IndexSet locally\_owned}, the \texttt{IndexSet locally\_relevant}, and
a boolean flag, whether to initialize the vector in the read-only or the write-only state.
- \item A vector created without providing a \texttt{IndexSet locally\_relevant} is purely local and cannot access non-local indices.
- Such a vector can not be copied to a vector that can access non-local indices, as the \texttt{IndexSet locally\_relevant} must
+ \item A vector created without providing the \texttt{IndexSet locally\_relevant} is purely local and cannot access non-local indices.
+ Such a vector cannot be copied to a vector that can access non-local indices, as the \texttt{IndexSet locally\_relevant} must
be provided at creating the vector object.
\item Some of solver and preconditioner parameters are not available in \tpetra{},
such that the \texttt{AdditionalData} objects are not identical.
programs:
\begin{itemize}
\item
- \texttt{step-83}
+ \step{83}
demonstrates how one can implement
checkpoint/restart functionality in \dealii-based programs,
using the \boost{} serialization functionality as a
- foundation. step-83 was written by Pasquale Africa, Wolfgang
- Bangerth, and Bruno Blais using step-19 as its basis.
+ foundation. \step{83} was written by Pasquale Africa, Wolfgang
+ Bangerth, and Bruno Blais using \step{19} as its basis.
\todo{Also add affiliations like for the other tutorials?}
\item
- \texttt{step-86}
+ \step{86}
is a program that solves the heat equation using \petsc's \ts{} (time
stepping) framework for the solution of ordinary differential
equations. Written by Wolfgang Bangerth (Colorado State
time stepping routines (such as wanting to change the mesh every
once in a while, or having to deal with boundary conditions).
\item
- \texttt{step-87} was contributed by Magdalena Schreter-Fleischhacker
+ \step{87}~\cite{schreter2023step87} was contributed by Magdalena Schreter-Fleischhacker
(Technical University of Munich) and Peter Munch
(University of Augsburg/Uppsala University). It
presents the advanced point-evaluation functionalities of \dealii,
which are useful for evaluating finite element solutions at
- arbitrary points on meshes that can be distributed among processes.
+ arbitrary points on meshes that can be distributed among processes. The presented mini-examples are motivated by the application to two-phase-flow simulations and demonstrate, for example, the evaluation of solution quantities at a surface mesh embedded in a background mesh, as is the case in front-tracking.
\item
- \texttt{step-89} was contributed by Johannes Heinz (TU Wien),
+ \step{89} was contributed by Johannes Heinz (TU Wien),
Maximilian Bergbauer (Technical University of Munich),
Marco Feder (SISSA), and Peter Munch (University of Augsburg/Uppsala University).
It shows a way how to apply non-matching and/or Chimera methods
within matrix-free loops in \dealii.
\item
- \texttt{step-90} was contributed by Vladimir Yushutin and Timo Heister (Clemson University).
+ \step{90} was contributed by Vladimir Yushutin and Timo Heister (Clemson University).
It implements the trace finite element method (TraceFEM). TraceFEM solves PDEs
posed on a, possibly evolving, $(dim-1)$-dimensional surface $\Gamma$ employing
a fixed uniform background mesh of a $dim$-dimensional domain in which
\item \dealii{} now requires compilers to support C++17, and has
started to extensively use C++17 features.
\item The \texttt{CUDAWrappers} namespace and its contents --
- notably things that enable the usage of cuSPARSE algorithms --
+ notably things that enable the usage of \texttt{cuSPARSE} algorithms --
have been deprecated and will be removed in the next
release. \kokkos{} is now used for device-specific optimizations.
\end{itemize}
University and Research (MUR), under the grant MUR PRIN 2022 No. 2022WKWZA8
``Immersed methods for multiscale and multiphysics problems (IMMEDIATE)''.
-Sebastian Kinnewig is supported by the Deutsche Forschungsgemeinschaft (DFG) under Germany’s Excellence
+S.~Kinnewig was supported by the Deutsche Forschungsgemeinschaft (DFG) under Germany’s Excellence
Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453)
M.~Kronbichler and P.~Munch were partially supported by the
projects / release-papers.git / commitdiff