Changeset 2357

Timestamp:

Feb 8, 2006, 3:41:01 PM (18 years ago)

Author:

sexton

Message:

Howard's first stab at Sydney example

File:

• documentation/AnuGA_user_manual.tex (modified) (2 diffs)

documentation/AnuGA_user_manual.tex

@@ -459 +459 @@
 
 \begin{itemize}
-\item{from a Windows command line} as in \texttt{python bedslope.py}
+\item{from a Windows command line} as in \code{python bedslope.py}
 
 \item{within the Python IDLE environment}
@@ -465 +465 @@
 \item{within emacs}
 
-\item{from a Linux command line} as in \texttt{python bedslope.py}
+\item{from a Linux command line} as in \code{python bedslope.py}
 \end{itemize}
 
 
-
+\section{Example with real data}
+
+The following discussion builds on the \code{bedslope.py} example and shows 
+how, using the same basic outline, we can incorporate many more complex features. 
+
+The chief difference is in the method used to create the mesh. Instead of imposing a mesh
+structure on a rectangular grid, the technique used for this example involves building 
+mesh structures inside polygons. 
+
+In its simplest form, the mesh is created within a 
+single polygon whose vertices are at geographical locations specified by the user. 
+A triangular mesh is created using points inside the polygon selected 
+through a random process, the
+user specifying the \emph{resolution}---that is, the maximal area of a triangle used for triangulation.
+
+Figure XXX shows a simple example, in which the triangulation is carried out within a 
+pentagon. Instead of using the four tags \texttt{`left'}, \texttt{`right'}, \texttt{`bottom'} and 
+\texttt{`top'} to distinguish
+boundary elements, the user can define tags appropriate to the configuration being modelled. 
+
+While this offers more flexibility than the rectangular grid, it doesn't provide a way to
+adapt to geographic 
+or other features in the landscape, for which we may require to vary the resolution. We achieve 
+more flexibility by extending this method, allowing the user to specify a number of 
+interior polygons which are triangulated separately, possibly using different resolutions. 
+See Figure XXX. 
 
 \appendix