[GRASS-SVN] r65075 - grass-addons/grass7/vector/v.isochrones

[svn_grass at osgeo.org]

Author: mlennert
Date: 2015-04-16 02:30:37 -0700 (Thu, 16 Apr 2015)
New Revision: 65075

Modified:
   grass-addons/grass7/vector/v.isochrones/v.isochrones.html
   grass-addons/grass7/vector/v.isochrones/v.isochrones.py
Log:
Correction of parameter description and more detailed description of the v.net.iso method


Modified: grass-addons/grass7/vector/v.isochrones/v.isochrones.html
===================================================================
--- grass-addons/grass7/vector/v.isochrones/v.isochrones.html	2015-04-16 08:04:22 UTC (rev 65074)
+++ grass-addons/grass7/vector/v.isochrones/v.isochrones.html	2015-04-16 09:30:37 UTC (rev 65075)
@@ -3,7 +3,7 @@
 <em>v.isochrones</em> creates a vector polygon map of isochrones 
 (<b>isochrones</b>) based on a roads map (<b>map</b>) with speed 
 or cost attribute (<b>cost_column</b>), one or several starting points 
-(<b>start_points</b>) and time steps for the isochrones 
+(<b>start_points</b>) and time steps (in minutes) for the isochrones 
 (<b>time_steps</b>). The module is actually a front-end to different 
 GRASS GIS modules, and the user can chose the approach with the <b>method</b> option
 (see the notes section for details).
@@ -20,8 +20,11 @@
 road segment that is within a given distance (<b>max_distance</b>). The <b>-i</b> flag allows
 to calculate a separate isochrone map for each starting point.
 For this approach, the input road map currently has to be prepared by adding all nodes (using 
-<em><a href="v.net">v.net</a></em> with 'operation=nodes' and the '-c' flag. In addition
-and a <b>cost_column</b> has to be present in the attribute table containing for each line segment 
+<em><a href="v.net">v.net</a></em> with 'operation=nodes' and the '-c' flag. 
+For each starting point, the algorithm then finds the closest node on the network 
+and calculates the isochrones from there. This allows to use the same network for 
+many analyses without having to go through the time of adding the starting points 
+at each run. In addition, a <b>cost_column</b> has to be present in the attribute table containing for each line segment 
 the time of traversal in minutes (i.e. length/speed).
 
 <p>

Modified: grass-addons/grass7/vector/v.isochrones/v.isochrones.py
===================================================================
--- grass-addons/grass7/vector/v.isochrones/v.isochrones.py	2015-04-16 08:04:22 UTC (rev 65074)
+++ grass-addons/grass7/vector/v.isochrones/v.isochrones.py	2015-04-16 09:30:37 UTC (rev 65075)
@@ -52,7 +52,7 @@
 #%option
 #% key: time_steps
 #% type: double
-#% description: Time steps of isochrones (in units defined by unit parameter)
+#% description: Time steps of isochrones (in minutes)
 #% multiple: yes
 #% required: yes
 #%end