[GRASS-SVN] r29443 - grass/trunk/raster/r.buffer

[svn_grass at osgeo.org]

Author: epatton
Date: 2007-12-15 09:54:38 -0500 (Sat, 15 Dec 2007)
New Revision: 29443

Modified:
   grass/trunk/raster/r.buffer/description.html
Log:
Clarity improvements; described -z flag, units parameter

Modified: grass/trunk/raster/r.buffer/description.html
===================================================================
--- grass/trunk/raster/r.buffer/description.html	2007-12-15 14:51:48 UTC (rev 29442)
+++ grass/trunk/raster/r.buffer/description.html	2007-12-15 14:54:38 UTC (rev 29443)
@@ -37,14 +37,14 @@
 ("Continuous" is used in the sense that each category
 zone's lower value is the previous zone's upper value. The
 first buffer zone always has distance <tt>0</tt> as its lower
-bound.) Distances can be entered in one of five units:
-<EM>meters, kilometers, feet, miles</EM>, and <EM>nautmiles</EM>
+bound.) Buffer distances can be specified using one of five units with the <EM>
+units</EM> parameter: <EM>meters, kilometers, feet, miles</EM>, and <EM>nautmiles</EM>
 (nautical miles).
 <P>
 
 <!-- ??? is this the real method used or some ancient option ??? -->
 Distances from cells containing the user-specified category values
-are calculated using the "fromcell" method. This method goes to each
+are calculated using the "fromcell" method. This method locates each
 cell that contains a category value from which distances are to be
 calculated, and draws the requested distance rings around
 them. This method works very fast when there are few cells
@@ -65,8 +65,12 @@
 category values, the user should run (for example) 
 <EM><A HREF="r.reclass.html">r.reclass</A></EM> prior to 
 <EM>r.buffer</EM>, to reclass all categories from which distance zones 
-are not desired to be calculated into category NULL.
+are not desired to be calculated into category NULL. 
+<P>
 
+The <B>-z</B> flag can be used to ignore raster values of zero instead of NULL
+values in the input raster map.
+<P>
 
 <H2>EXAMPLE</H2>