Hello to the GRASS users,
I have a question about interpolating surface from vector points. I’m building surface for a large area 8x10km with IDW method, from point data derived from LiDAR.
There is large area at the south-east side in the dataset (probably 1/3 of the whole set) with no data and also some small gaps in the data (in place of buildings). What to do when interpolating because the program interpolates also in the large ‘no data’ area resulting in flat surfaces and strange shapes there? How to proceed in this case?
Greetings,
Adrian Kirilov
On Mon, May 6, 2013 at 4:59 PM, Adrian Kirilov <kirilov.adrian@gmail.com> wrote:
Hello to the GRASS users,
I have a question about interpolating surface from vector points. I'm
building surface for a large area 8x10km with IDW method, from point data
derived from LiDAR.
IDW is not the best method for many cases. Please take a look here:
http://grasswiki.osgeo.org/wiki/Interpolation
(yes, that page could be still improved)
There is large area at the south-east side in the dataset (probably
1/3 of the whole set) with no data and also some small gaps in the data (in
place of buildings). What to do when interpolating because the program
interpolates also in the large 'no data' area resulting in flat surfaces and
strange shapes there? How to proceed in this case?
You may try v.surf.bspline instead which uses B-splines rather than IDW.
Markus