Re: [ferret_users] shade 3 args with time

[Ansley Manke <ansley.b.manke@xxxxxxxx>]

Hi Patrick,
I think we could probably do this but first I want to understand more about your grid. Is your grid actually curvilinear in longitude-time?  Or are you thinking of plots using the 2-dimensional longitude coordinates from a grid that is curvilinear in xy and a time variable that is somehow generated?

If the curvilinear nature of the grid is in the horizontal dimensions, then to make a Hovmoller plot in X-T, I think you'd want to use the curvilinear sampling function, SAMPLEXY_CURV, to get a subset of the data at a particular latitude, and then plot that. So if your data looks like

yes? show data
     currently SET data sets:
    1> ./curvi_data.nc  (default)
 name     title                     I         J         K         L
 U        zonal current            1:360     1:180     1:1       1:123
 GEOLON   longitude                1:360     1:180     ...       ...
 GEOLAT   latitude                 1:360     1:180     ...       ...

you could define some longitude and latitude pairs to sample:

let xpts = x[x=2:360:2]
let ypts = 0* xpts + 31.

let u_at_31N = samplexy_curv(u, geolon, geolat, xpts, ypts)

This would return U sampled at each of the longitude-latitude locations (2,31), (4,31) , ... (360,31), for all times on the time axis of U. The result of the function is on an abstract axis in the X direction, so you would need to define the equivalent longitude axis, and put u_at_31N onto that axis, and then you could plot it as a longitude-time plot with  the regular 1-argument plot commands.

Ansley



Brockmann Patrick wrote:

Hi all,

Is there a way to activate time labeling when a shade command is used with 3 args ?
It would be usefull to plot hovmoller plot from curvilinear model output.

Attached is a script using classic navy_winds netcdf file to simulate the problem.
Thanks

Patrick