[Gdal-dev] down sample question

[Norman Vine]

Clay, Bruce writes:
> 
> New question...
> 
> Does anyone have a routine to share that given a data set in memory that
> performs any form of interpolation to determine the elevation at a
> particular latitude and longitude?  I assume this requires interpolation
> from the latitude north and south the desired point as well as the
> longitude east and west of the desired point.

I suggest just using simple bilinear interpolation to start with, for this,
you will need to determine the 4 points from your elevation grid that
describes the 'box' that contains your query point and then interpolate 
between them.

HTH

Norman