[gradsusr] map projection error: invalid coords for nps

[mberdahl at envsci.rutgers.edu]

Hi all,

I am trying to plot some wind vectors in GrADS from a netcdf file, on a
polar stereographic projection, but I receive the following error:

Map Projection Error:  Invalid coords for NPS
  Will use linear lat-lon projection

A nice lat/lon plot is produced without a problem, but any other
projection I choose gives the above error.

I have copied my ctl file and the grads commands I execute below.
Does anyone have any thoughts on how to resolve this issue?

Many thanks!
Mira


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
GrADS commands:

reinit

*what file to open
open MPI_wind_diff.ctl

*set projection, display background, and resolution of background
set display color white
set background 1
set mpdset hires
set mproj nps
set grid on
set gxout vector

d uaDiff;vaDiff
set arrlab on

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
CTL FILE:

dset ^MPI_wind_diff.nc
dtype netcdf
title Difference between ua and va for LIA to MCA periods
undef -999
xdef 192 linear  0 1.875
ydef 96  linear  -88.5721664428711 1.8496
tdef  1 linear 06Z01JAN1400  1mo
zdef  1 levels 500
vars 4
longitude=>lon 1 y,x **longitude
latitude=>lat 1 y,x **latitude
uaDiff=>uaDiff 1 y,x **ua difference (m/s)
vaDiff=>vaDiff	1 y,x ** va difference (m/s)
endvars