[GRASS-SVN] r59149 - grass/trunk/raster/r.slope.aspect
svn_grass at osgeo.org
svn_grass at osgeo.org
Fri Feb 28 13:55:29 PST 2014
Author: martinl
Date: 2014-02-28 13:55:28 -0800 (Fri, 28 Feb 2014)
New Revision: 59149
Modified:
grass/trunk/raster/r.slope.aspect/main.c
grass/trunk/raster/r.slope.aspect/r.slope.aspect.html
Log:
r.slope.aspect: manual cosmetics
Modified: grass/trunk/raster/r.slope.aspect/main.c
===================================================================
--- grass/trunk/raster/r.slope.aspect/main.c 2014-02-28 11:32:05 UTC (rev 59148)
+++ grass/trunk/raster/r.slope.aspect/main.c 2014-02-28 21:55:28 UTC (rev 59149)
@@ -151,7 +151,7 @@
G_add_keyword(_("raster"));
G_add_keyword(_("terrain"));
module->label = _("Generates raster maps of slope, aspect, curvatures and "
- "partial derivatives from a elevation raster map.");
+ "partial derivatives from an elevation raster map.");
module->description = _("Aspect is calculated counterclockwise from east.");
parm.elevation = G_define_standard_option(G_OPT_R_ELEV);
@@ -256,7 +256,7 @@
flag.a = G_define_flag();
flag.a->key = 'a';
flag.a->description =
- _("Do not align the current region to the elevation layer");
+ _("Do not align the current region to the raster elevation map");
flag.a->guisection = _("Settings");
Modified: grass/trunk/raster/r.slope.aspect/r.slope.aspect.html
===================================================================
--- grass/trunk/raster/r.slope.aspect/r.slope.aspect.html 2014-02-28 11:32:05 UTC (rev 59148)
+++ grass/trunk/raster/r.slope.aspect/r.slope.aspect.html 2014-02-28 21:55:28 UTC (rev 59149)
@@ -1,30 +1,34 @@
<h2>DESCRIPTION</h2>
-<b>r.slope.aspect </b>generates raster maps of slope, aspect, curvatures and
+<em>r.slope.aspect</em> generates raster maps of slope, aspect, curvatures and
first and second order partial derivatives from a raster map of true
-elevation values. The user must specify the input <i>elevation</i> file name
-and at least one output file name. The user can also specify the
-<i>format</i> for slope (degrees, percent; default=degrees), and the
-<i>zfactor</i>: multiplicative factor to convert elevation units to meters;
+elevation values. The user must specify the input <b>elevation</b> raster map
+and at least one output raster maps. The user can also specify the
+<b>format</b> for slope (degrees, percent; default=degrees), and the
+<b>zfactor</b>: multiplicative factor to convert elevation units to meters;
(default 1.0).
+
<p>
-The <i>elevation</i> input raster map specified by the user must contain true
-elevation values, <b>not</b> rescaled or categorized data. If the elevation
+The <b>elevation</b> input raster map specified by the user must contain true
+elevation values, <em>not</em> rescaled or categorized data. If the elevation
values are in feet or other units than meters (with a conversion factor
<i>meters:</i>, defined in PROJ_UNITS), they must be converted to meters using
-the parameter <i>zfactor</i>.
+the parameter <b>zfactor</b>.
+
<p>
-The <i>aspect</i> output raster map indicates the direction that slopes are
+The <b>aspect</b> output raster map indicates the direction that slopes are
facing. The aspect categories represent the number degrees of east. Category
-and color table files are also generated for the aspect map layer. The aspect
+and color table files are also generated for the aspect raster map. The aspect
categories represent the number degrees of east and they increase
counterclockwise: 90deg is North, 180 is West, 270 is South 360 is East. The
aspect value 0 is used to indicate undefined aspect in flat areas with slope=0.
+
<p>
-The <i>slope</i> output raster map contains slope values, stated in degrees of
-inclination from the horizontal if <i>format</i>=degrees option (the default)
-is chosen, and in percent rise if <i>format</i>=percent option is chosen.
+The <b>slope</b> output raster map contains slope values, stated in degrees of
+inclination from the horizontal if <b>format</b>=degrees option (the default)
+is chosen, and in percent rise if <b>format</b>=percent option is chosen.
Category and color table files are generated.
+
<p>
Profile and tangential curvatures are the curvatures in the direction of
steepest slope and in the direction of the contour tangent respectively. The
@@ -84,7 +88,7 @@
<p>For some applications, the user will wish to use a reclassified raster map
of slope that groups slope values into ranges of slope. This can be done using
-<i><a href="r.reclass.html">r.reclass</a></i>. An example of a useful
+<em><a href="r.reclass.html">r.reclass</a></em>. An example of a useful
reclassification is given below:
<div class="code"><pre> category range category labels
(in degrees) (in percent)
@@ -114,23 +118,23 @@
<h2>NOTES</h2>
-To ensure that the raster elevation map layer is not inappropriately resampled,
+To ensure that the raster elevation map is not inappropriately resampled,
the settings for the current region are modified slightly (for the execution
of the program only): the resolution is set to match the resolution of
-the elevation map and the edges of the region (i.e. the north, south, east
+the elevation raster map and the edges of the region (i.e. the north, south, east
and west) are shifted, if necessary, to line up along edges of the nearest
-cells in the elevation map. If the user really wants the elevation map
-resampled to the current region resolution, the -a flag should be specified.
+cells in the elevation map. If the user really wants the raster elevation map
+resampled to the current region resolution, the <b>-a</b> flag should be specified.
<p>
The current mask is ignored.
<p>
The algorithm used to determine slope and aspect uses a 3x3 neighborhood
-around each cell in the elevation file. Thus, it is not possible to determine
+around each cell in the raster elevation map. Thus, it is not possible to determine
slope and aspect for the cells adjacent to the edges in the elevation map
layer. These cells are assigned a "zero slope" value (category 0) in both
-the slope and aspect raster map layers.
+the slope and aspect raster maps.
<p>
Horn's formula is used to find the first order derivatives in x and y directions.
@@ -145,9 +149,9 @@
Because most cells with a very small slope end up having category 0,
45, ..., 360, it is sometimes possible to reduce the bias in these directions
by filtering out the aspect in areas where the terrain is almost flat. A new
-option <i>min_slp_allowed</i> was added to specify the minimum slope for which
+option <b>min_slp_allowed</b> was added to specify the minimum slope for which
aspect is computed. The aspect for all cells with slope <
-<i>min_slp_allowed</i> is set to <b>null</b>.
+<b>min_slp_allowed</b> is set to <i>null</i> (no-data).
<h2>REFERENCE</h2>
@@ -166,13 +170,16 @@
<h2>SEE ALSO</h2>
-<em><a href="r.mapcalc.html">r.mapcalc</a></em>,
-<em><a href="r.neighbors.html">r.neighbors</a></em>,
-<em><a href="r.reclass.html">r.reclass</a></em>,
-<em><a href="r.rescale.html">r.rescale</a></em>
+<em>
+ <a href="r.mapcalc.html">r.mapcalc</a>,
+ <a href="r.neighbors.html">r.neighbors</a>,
+ <a href="r.reclass.html">r.reclass</a>,
+ <a href="r.rescale.html">r.rescale</a>
+</em>
<h2>AUTHORS</h2>
+
Michael Shapiro, U.S.Army Construction Engineering Research Laboratory<br>
Olga Waupotitsch, U.S.Army Construction Engineering Research Laboratory
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