From 1d2d566d9c8a8998148b220ff9834de714ffd275 Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Mon, 23 Apr 2018 16:06:05 -0600 Subject: [PATCH] Work through the incompatibilities section. --- 9.0/paper.tex | 68 ++++++++++++++++++++++++++++++++------------------- 1 file changed, 43 insertions(+), 25 deletions(-) diff --git a/9.0/paper.tex b/9.0/paper.tex index bcfce8d..5348035 100644 --- a/9.0/paper.tex +++ b/9.0/paper.tex @@ -263,6 +263,7 @@ the release announcement.) %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \subsection{xxx something with Manifolds xxx} +\label{sec:manifolds} \marginpar{All: please edit as appropriate} @@ -402,7 +403,8 @@ functionality is now available via \dealii{} interfaces. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -\subsection{Use of C++11} + \subsection{Use of C++11} + \label{sec:cxx11} \dealii{} first offered support for a subset of C++11 features in version 6.2, released in 2009. The current release is the first to \emph{require} a C++11 compiler. @@ -460,34 +462,50 @@ With these additions, the code gallery now contains 10 different applications. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \subsection{Incompatible changes} -\marginpar{OLD} -The 9.0 release includes around XYZ -\href{https://www.dealii.org/developer/doxygen/deal.II/changes_between_8_5_and_9_0.html}{ -incompatible changes}; see \cite{changes90}. The majority of these changes +The 9.0 release includes +\href{https://www.dealii.org/developer/doxygen/deal.II/changes_between_8_5_and_9_0.html} + {around 75 incompatible changes}; see \cite{changes90}. The majority of these changes should not be visible to typical user codes; some remove previously deprecated classes and functions, and the majority change internal -interfaces that are not usually used in external applications. However, three +interfaces that are not usually used in external +applications. However, some are, such as changes to the interplay between meshes and +manifolds, as well as the requirement to use a +C++11 compiler (see Sections~\ref{sec:manifolds} and +~\ref{sec:cxx11}). In addition, the following incompatible changes are worth mentioning: \begin{itemize} - \item High-order Lagrange elements, both continuous \verb!FE_Q! and - discontinuous \verb!FE_DGQ! types, now use the nodal points of the - Gauss-Lobatto quadrature formula as support points by default, rather than the - previous equidistant ones. For cubic polynomials and higher, the point - distribution has thus changed and, consequently, the entries in - solution vectors will be different compared to previous - versions of \dealii{}. Note, however, that using the Gauss-Lobatto points as nodal - points results in a much more stable interpolation, including better - iteration counts in most iterative solvers. - \item - The library no longer instantiates template classes with \texttt{long - double}. These were rarely used, but took up a significant - fraction of compile and link time, as well as library - size. Application programs can, however, still instantiate all - template classes with \texttt{long - double} as long as they include the corresponding \texttt{.templates.h} - header files. - \item - The \texttt{ParameterGUI} has been moved to a separate repository. +\item The \texttt{BlockDiagonalMatrix}, + \texttt{InverseMatrixRichardson}, + \texttt{IterativeInverse}, + \texttt{ProductMatrix}, + \texttt{ProductSparseMatrix}, + \texttt{TransposeMatrix}, + \texttt{ScaledMatrix}, + \texttt{SchurMatrix}, + \texttt{ShiftedMatrix}, and + \texttt{ShiftedMatrixGeneralized} classes have been removed. They are now + generalized through the \texttt{LinearOperator} concept. Several + other, similar classes have been deprecated. + + \item The default partitioner for the + \texttt{parallel::shared::Triangulation} is now the Trilinos + package Zoltan. This functionality was previously provided by the + METIS partitioner, but the METIS package has not been actively maintained + for a long time, and moreover yields subdivisions that depend on + system details such as the random number generator and sorting + facilities provided by the operating system; consequently, the + partition is not consistent across platforms. + + \item The class \texttt{FE\_DGQHermite} now uses a more stable, + ``Hermite-like'' polynomial basis. The change is highly + beneficial because it significantly improves the accuracy (in + terms of roundoff) for this basis and also reduces iteration + counts for some iterative solvers with simple preconditioners. + + \item Many functions that previously returned a raw, C-style pointer + now return a \texttt{std::unique\_ptr} and + \texttt{std::shared\_ptr} where possible to make memory management + more reliable. \end{itemize} -- 2.39.5