[GRASS-user] r.stream.basins

I am having problems with r.stream basins. I am trying to delineate
watersheds above GPSed points. About half of the watersheds are being
delineated satisfactorily. The others are very small sub watersheds
that are not the correct contributing areas. I imagine that this is
because the point is not exactly on the stream? I am using
r.watershed to produce the direction map and using a vector layer with
points GPSed in the field. Any thoughts would be appreciated.
kind regards,

--
Stephen Sefick

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods. We are mammals, and have not exhausted the
annoying little problems of being mammals.

                -K. Mullis

The points need to coincide with a nearby high value accumulation cell.

Mark

On Jan 28, 2010, at 4:22 PM, stephen sefick <sas0025@auburn.edu> wrote:

I am having problems with r.stream basins. I am trying to delineate
watersheds above GPSed points. About half of the watersheds are being
delineated satisfactorily. The others are very small sub watersheds
that are not the correct contributing areas. I imagine that this is
because the point is not exactly on the stream? I am using
r.watershed to produce the direction map and using a vector layer with
points GPSed in the field. Any thoughts would be appreciated.
kind regards,

--
Stephen Sefick

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods. We are mammals, and have not exhausted the
annoying little problems of being mammals.

                               -K. Mullis
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grass-user@lists.osgeo.org
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Thanks for the response - I moved the values to the closest synthetic
stream, and it worked without a hitch. Thank you again for your time.
kindest regards,

Stephen

On Thu, Jan 28, 2010 at 6:37 PM, MS <mseibel@gmail.com> wrote:

The points need to coincide with a nearby high value accumulation cell.

Mark

On Jan 28, 2010, at 4:22 PM, stephen sefick <sas0025@auburn.edu> wrote:

I am having problems with r.stream basins. I am trying to delineate
watersheds above GPSed points. About half of the watersheds are being
delineated satisfactorily. The others are very small sub watersheds
that are not the correct contributing areas. I imagine that this is
because the point is not exactly on the stream? I am using
r.watershed to produce the direction map and using a vector layer with
points GPSed in the field. Any thoughts would be appreciated.
kind regards,

--
Stephen Sefick

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods. We are mammals, and have not exhausted the
annoying little problems of being mammals.

                          \-K\. Mullis

_______________________________________________
grass-user mailing list
grass-user@lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/grass-user

--
Stephen Sefick

Let's not spend our time and resources thinking about things that are
so little or so large that all they really do for us is puff us up and
make us feel like gods. We are mammals, and have not exhausted the
annoying little problems of being mammals.

                -K. Mullis

stephen sefick pisze:

Thanks for the response - I moved the values to the closest synthetic
stream, and it worked without a hitch. Thank you again for your time.
kindest regards,

Stephen

On Thu, Jan 28, 2010 at 6:37 PM, MS <mseibel@gmail.com> wrote:
  

The points need to coincide with a nearby high value accumulation cell.

r.astream.basins allow to make a 'trick' for such situation:

create buffer around GPS points, rasterise it and next use it raster as stream map. Note that every point shall have its own category

J.