Rotating nps

[Danny Blair]

Help!  I'm making northern hemisphere maps of various things, but can't
figure out how to rotate the nps projection so that North America is
vertical, north up.  A previous post suggests that I simply have to use
something like 'set lon -270 90', with the two numbers differing by no more
than 360, but that doesn't work; this does put North America in the correct
position, but the map is blank except for the wedge of longitudes between 0
and 90E.

Using GrADS 1.8SL11 on Linux.

The .ctl for the dataset looks like this:

dset          ^1000mb1950to2004.dat
undef         -9.99e+33
title         1950 to 2004 twice daily 1000mb hgt
xdef          145 linear 0 2.5
ydef          37 linear 0 2.5
tdef          40178 linear 00z01jan1950 12hr
zdef          1 levels 1000
vars          1
hgt           0 99 hgt mb height
endvars

This is merged reanalysis data (55 years, 00z and 12z), north hem only.

Cheers!