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revision 2680 by ahallam, Thu Sep 10 02:58:44 2009 UTC revision 2681 by ahallam, Thu Sep 24 03:04:04 2009 UTC
# Line 29  The \verb esys  library tree has \textbf Line 29  The \verb esys  library tree has \textbf
29  \item \modfinley is the discretisation tool and finite element package.  \item \modfinley is the discretisation tool and finite element package.
30  \item \modpycad  is a special development for creating irregular domains and models. That are easily interpretable by \esc .  \item \modpycad  is a special development for creating irregular domains and models. That are easily interpretable by \esc .
31  \end{enumerate}  \end{enumerate}
32  Further explanations on each of these is available in the user guide or in the API documentation at \url{https://launchpad.net/escript-finley/+download}. \ESCRIPT is also dependent on a few other open-source packages which are not maintained by the \ESCRIPT development team. These are \modnumpy an array and matrix handling package, \modmpl a simple plotting and visualisation tool, \modvtk  the advanced plotting and visualisation package and \verb gmsh  which is required by \modpycad. These packages (\textbf{except} for \verb gmsh ) are included with the binary release but may not be the most recent and up to date.  Further explanations on each of these is available in the \esc user guide or in the API documentation at \url{https://launchpad.net/escript-finley/+download}. \ESCRIPT is also dependent on a few other open-source packages which are not maintained by the \ESCRIPT development team. These are \modnumpy an array and matrix handling package, \modmpl a simple plotting and visualisation tool, \modvtk  the advanced plotting and visualisation package and \verb gmsh  which is required by \modpycad. These packages (\textbf{except} for \verb gmsh ) are included with the binary release but may not be the most recent and up to date.
33    
34  \subsection{The Domain Constructor in \ESCRIPT}  \subsection{The Domain Constructor in \ESCRIPT}
35  \label{ss:domcon}  \label{ss:domcon}
36  It is important at this paticular stage to describe how domains and data are organised and related to each other in escript.  It is important at this paticular stage to describe how domains and data are organised and related to each other in escript.
37  \begin{figure}[t]  \begin{figure}[t]
38   \centering   \centering
39     \includegraphics[width=4in]{figures/functionspace}     \includegraphics[width=6in]{figures/functionspace.pdf}
40     \label{fig:fs}     \label{fig:fs}
41     \caption{\ESCRIPT domain construction overview}     \caption{\ESCRIPT domain construction overview}
42  \end{figure}  \end{figure}
# Line 48  When the domain variables are submitted Line 48  When the domain variables are submitted
48  \end{enumerate}  \end{enumerate}
49  Domains in \ESCRIPT are constructed this way to allow for varying degrees of smoothness in a PDE problem. That is, the continuity of the first derivative of each data input. For example, the coefficients of a PDE need not be continuous, thus this qualifies as a \verb Function()  type, while a temperature distribution must be a \verb ContinuousFunction()  and a flux condition may only exist at a boundary as a \verb FunctionOnBoundary()  .  The domain constructor is able to interpret the data in each of these situations for the solver so that a solution can be produced. It should be noted that a solution has its own function space \verb Solution()  which is located depending on the required output. The domain also allows certain transformations of the function spaces. A \verb ContinuousFunction()  can be transformed into a \verb FunctionOnBoundary()  or \verb Function() . On the other hand there is not enough information in a \verb FunctionOnBoundary()  to transform it to a \verb ContinuousFunction()  .  Domains in \ESCRIPT are constructed this way to allow for varying degrees of smoothness in a PDE problem. That is, the continuity of the first derivative of each data input. For example, the coefficients of a PDE need not be continuous, thus this qualifies as a \verb Function()  type, while a temperature distribution must be a \verb ContinuousFunction()  and a flux condition may only exist at a boundary as a \verb FunctionOnBoundary()  .  The domain constructor is able to interpret the data in each of these situations for the solver so that a solution can be produced. It should be noted that a solution has its own function space \verb Solution()  which is located depending on the required output. The domain also allows certain transformations of the function spaces. A \verb ContinuousFunction()  can be transformed into a \verb FunctionOnBoundary()  or \verb Function() . On the other hand there is not enough information in a \verb FunctionOnBoundary()  to transform it to a \verb ContinuousFunction()  .
50    
51  The domain also handles an ability of \ESCRIPT known as tagging which allows areas and lines to be given a name for easier referencing later on.  The domain also handles an ability of \ESCRIPT known as tagging, which allows areas and lines to be given a name for easier referencing later on.
52    
53  \subsection{File Commands and Operations in \ESCRIPT}  \subsection{File Commands and Operations in \ESCRIPT}
54  A number of common file operations and commands are used throughout this cookbook. It is often advantageous to implement these commands when large numbers of output files are generated or dependencies are located in other locations.  A number of common file operations and commands are used throughout this cookbook. It is often advantageous to implement these commands when large numbers of output files are generated or dependencies are located in other locations.
# Line 84  A subfolder check/constructur is availab Line 84  A subfolder check/constructur is availab
84  \begin{verbatim}  \begin{verbatim}
85  needdirs(save_path)  needdirs(save_path)
86  \end{verbatim}  \end{verbatim}
87  will check for the existence of \verb save_path  and if needed, make the required directories.  will check for the existence of \verb save_path  and if missing, make the required directories.
88    
89    
90  \subsection{Visualisation and Plotting}  \subsection{Visualisation and Plotting}
91  \ESCRIPT does not include its own plotting capabilities however it works with a number of free visualisation systems.  \ESCRIPT does not include its own plotting capabilities however it works with a number of free visualisation systems.
92  We will dicsuss two types of systems in this document: \mpl\footnote{\url{http://matplotlib.sourceforge.net/}} and \verb VTK \footnote{\url{http://www.vtk.org/}} visualisation.  We will dicsuss two types of systems in this document: \mpl\footnote{\url{http://matplotlib.sourceforge.net/}} and \verb VTK \footnote{\url{http://www.vtk.org/}} visualisation.
 The \mpl package is based on the \numpy array package and is good for basic graphs and plots. The \verb VTK  toolkit allows the \esc data to be exported in a standardised format with powerful visualisation capabilities. This format can be interpreted by many programs. In this cookbook \mayavi \footnote{\url{http://code.enthought.com/projects/mayavi/}} will be used to visualise \verb VTK  files.  
93    The \mpl package is a part of SciPy\footnote{\url{http://www.scipy.org}} and is good for basic graphs and plots. The \verb VTK  toolkit allows the \esc data to be exported in a standardised format with powerful visualisation capabilities. This format can be interpreted by many programs. In this cookbook \mayavi \footnote{\url{http://code.enthought.com/projects/mayavi/}} will be used to visualise \verb VTK  files.

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