translating coordinates and slanted hovmollers

[John Murray]

Hello GrADS users,

I was wondering if anyone knew how to translate a dataset east or west from
its original coordinates.  I want to basically have a modified longitude
axis from which I can plot a hovmoller diagram.  The modified longitude is
for purposes of making the terrain across an area more straight and the
coastline more meridonal for the hovmoller diagram. The new longitude would
be equal to the old longitude+(lat1-lat2)*a factor. In that way, a hovmoller
could plot something that is more perpendicular to the terrain.  I can
successfully define a new variable which is oriented slantwise, but how
would you define a new x-axis?  Would this require a change in the control
file, or could you redefine the data slantwise without changing the control
file?

For example, the data for point (1,2) would be relocated to (2,2); the data
for point (1,3) would be relocated to (3,3) as shown below,

before:

1 2
1 2
1 2

after:

x x 1 2
x 1 2 x
1 2 x x

Thanks

John