From 64f322edca840529a0ecd6e897490e345e4be26f Mon Sep 17 00:00:00 2001 From: Paul Garlick Date: Wed, 15 Jul 2020 14:41:01 +0100 Subject: doc: Add plots demonstrating the use of slope.py. * doc/fullswof-utils.texi (Demos): Add sample plots. --- doc/fullswof-utils.texi | 45 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 38 insertions(+), 7 deletions(-) diff --git a/doc/fullswof-utils.texi b/doc/fullswof-utils.texi index bf39498..4e51a5e 100644 --- a/doc/fullswof-utils.texi +++ b/doc/fullswof-utils.texi @@ -376,13 +376,44 @@ also provided. To run the demos directly, first change the current working directory to the @file{demo} directory. Then execute the individual program -(@pxref{Invoking makeBoundary} for an example). - -The input files may be viewed with a text editor. To experiment with -the control parameters, first back up the distributed input files and -then edit the parameter values as desired. Note that the -@command{makeBoundary} program will overwrite its output file if it -already exists. +(@pxref{Usage} for the command line syntax). + +The input files for @command{makeBoundary} may be viewed with a text +editor. To experiment with the control parameters, first back up the +distributed input files and then edit the parameter values as desired. +Note that the @command{makeBoundary} program will overwrite its output +file if it already exists. + +Running @command{slope.py} provides an opportunity to test the effect of +marker positioning. Contour plots of elevation and slope are displayed +when the @kbd{m} key is pressed. The elevation contour plot allows the +feature of interest to be identified. Markers are placed in pairs on +either side of the channel feature. An example of a set of marker pairs +is shown in @ref{fig:markers}. + +@float Figure,fig:markers + @center @image{./images/markers} + @caption{Contour plots of elevation (left) and slope (right). Feature markers are shown as red disks.} +@end float + +@command{slope.py} draws a straight line between each pair of markers. +A search procedure reveals the position along each line at which the +elevation is a minimum. The set of minumum positions identifies the +centre-line of the channel. The profile of the channel is plotted and +displayed when the @kbd{p} key is pressed. The profile calculated from +the markers shown in @ref{fig:markers} is shown in @ref{fig:profile}. + +@float Figure,fig:profile + @center @image{./images/profile} + @caption{Elevation plotted against distance from bottom boundary.} +@end float + +The blue line in @ref{fig:profile} shows the height variation of the +channel centre-line. The best-fit line is shown by the dashed red line. +The gradient of the best-fit line and the intercept on the y-axis are +printed to standard output. The data points that define the blue line +are written to the file @file{1D.txt} when the @kbd{s} key is pressed. +The file is overwritten if it already exists. @node GNU Free Documentation License, Index, Usage, Top @appendix GNU Free Documentation License -- cgit