[gradsusr] lterp+sdfwrite adding extra longitude values

[Andrew Friedman]

Hi GrADS users,

I am using lterp to regrid a file to a coarser resolution, and saving the variable to netcdf using sdfwrite.

My problem is that the output file has 2 additional longitudes compared to the input grid destination description file.

Similar to the example in the lterp documentation in the grads index:

sdfopen fine.nc
set X 1 [number of longitude points in fine.nc]
sdfopen coarse.nc
output = lterp(fine,coarse.2,aave)
set sdfwrite output.nc
sdfwrite output

I've had this issue before when there is just one input file, and explicitly defining longitude with the step 'set X 1 [number of longitude points]' works to solve it. In this case however, I'm not sure how to limit the longitude dimension of the output.
Do you have ideas how I can fix this?

Thanks,
Andrew


------
Andrew Friedman
Graduate Student, UC Berkeley Geography
andfried at berkeley.edu