Hi Markus,
Is sink filling discouraged or just not needed and optional? My impression is that r.watershed produces better results with not sink filled rasters, but sink filling doesn’t hurt much.
Thanks.
Huidae
···
On Tue, Jun 17, 2014 at 1:40 PM, <svn_grass@osgeo.org> wrote:
Author: neteler
Date: 2014-06-17 10:40:00 -0700 (Tue, 17 Jun 2014)
New Revision: 60855
Modified:
grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html
Log:
r.watershed manual: (minor) sync with trunk
Modified: grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html
— grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html 2014-06-17 17:39:37 UTC (rev 60854)
+++ grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html 2014-06-17 17:40:00 UTC (rev 60855)
@@ -55,7 +55,8 @@
values are valid elevation data. Gaps in the elevation map that are
located within the area of interest must be filled beforehand,
e.g. with r.fillnulls, to
-avoid distortions.
+avoid distortions. The elevation map need not be sink-filled because
+the module uses a least-cost algorithm.
Map of actual depressions or sinkholes in the landscape that are large
@@ -113,7 +114,7 @@
Output tci raster map contains topographic index TCI is
computed as
-ln(α / tan(β)) where α a is the cumulative
+ln(α / tan(β)) where α is the cumulative
upslope area draining through a point per unit contour length and
tan(β) is the local slope angle. The TCI reflects the
tendency of water to accumulate at any point in the catchment and the
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Hi Huidae,
Markus Metz is the expert here...
Best
MarkusN (just doing a lot of backporting)
On Thu, Jun 19, 2014 at 8:21 PM, Huidae Cho <grass4u@gmail.com> wrote:
Hi Markus,
Is sink filling discouraged or just not needed and optional? My impression
is that r.watershed produces better results with not sink filled rasters,
but sink filling doesn't hurt much.
Thanks.
Huidae
On Tue, Jun 17, 2014 at 1:40 PM, <svn_grass@osgeo.org> wrote:
Author: neteler
Date: 2014-06-17 10:40:00 -0700 (Tue, 17 Jun 2014)
New Revision: 60855
Modified:
grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html
Log:
r.watershed manual: (minor) sync with trunk
Modified:
grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html
---
grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html
2014-06-17 17:39:37 UTC (rev 60854)
+++
grass/branches/releasebranch_7_0/raster/r.watershed/front/r.watershed.html
2014-06-17 17:40:00 UTC (rev 60855)
@@ -55,7 +55,8 @@
values are valid elevation data. Gaps in the elevation map that are
located within the area of interest must be filled beforehand,
e.g. with <em><a href="r.fillnulls.html">r.fillnulls</a></em>, to
-avoid distortions.
+avoid distortions. The elevation map need not be sink-filled because
+the module uses a least-cost algorithm.
<p>
Map of actual depressions or sinkholes in the landscape that are large
@@ -113,7 +114,7 @@
<p>
Output <b>tci</b> raster map contains topographic index TCI is
computed as
-<tt>ln(α / tan(β))</tt> where α a is the cumulative
+<tt>ln(α / tan(β))</tt> where α is the cumulative
upslope area draining through a point per unit contour length and
<tt>tan(β)</tt> is the local slope angle. The TCI reflects the
tendency of water to accumulate at any point in the catchment and the
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