Tell me more ×
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It's 100% free, no registration required.
up vote 5 down vote favorite
2

I have a 3d raster dataset of atmospheric variables (lat x lon x altitude). I would like to sample this raster dataset along a 3d path.

Any idea how I can achieve this, preferable with qgis or postgis or rasdaman?

Edit: Actually, my data is 4d (time x lat x lon x altitude), but having a 3d solution would already be great.

share|improve this question
Could you please explain the sense in which a 3D "polygon" can be interpreted as a path? Do you mean that its boundary is intended as a path, or are you perhaps asking about sampling the raster throughout the polygon itself (including its interior)? And when you use "polygon," does that presuppose (as in the conventional mathematical sense) that it is planar? – whuber♦ Dec 5 '12 at 21:07
1  
@whuber of course you're right, this doesn't make sense. Forget about the polygon, I simply want to sample along a 3d path. – andreash Dec 5 '12 at 21:23
You probably need to bake your own trilinear interpolation routine with NumPy arrays. I have a bilinear interpolation solution for GDAL (2D) if you need inspiration. – Mike Toews Dec 5 '12 at 22:02
See also SciPy's multivariate interpolation functions, although I've experience some oddities. Worth checking though. – Mike Toews Dec 5 '12 at 22:46
thanks @MikeToews, I'm actually quite familiar with SciPy and interpolation ;) However, I didn't want to have to deal with projection issues etc. and thus would favour some GIS-based solution where I don't have to worry about such stuff. – andreash Dec 6 '12 at 6:54
show 1 more comment

Know someone who can answer? Share a link to this question via email, Google+, Twitter, or Facebook.

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.