[ncl-talk] Contour plot with rotated grid shifted to the west

[Mary Haley]

Guido,

I'm hoping Dave will weigh in here, but it would help if we could at least
see the output from:

ncl_filedump pv.nc

Sometimes the global attributes of the file will give some valuable
information about the correct map projection parameters.

Did you actually try commenting out the mpCenterLatF and mpCenterLonF
settings?  In the script you included, these two resources are still being
set.

It's possible that the data has already been rotated for you.

--Mary




On Mon, Nov 30, 2015 at 1:33 AM, Guido Cioni <guidocioni at gmail.com> wrote:

> Hi all,
> I’m trying to produce a contour plot with data on a rotated grid. The
> original data look like that
>
>
> Since I have the rotated north pole latitude (*44.999996*) and longitude (
> *144.0*) in my data file I used the second example of the support page on
> rotated grid.
>
>  Res1 at tfDoNDCOverlay=True
>  Res1 at mpLimitMode = "Corners"
>  Res1 at mpLeftCornerLatF = lat(0)
>  Res1 at mpLeftCornerLonF = lon(0)
>  Res1 at mpRightCornerLatF = lat(nlat-1)
>  Res1 at mpRightCornerLonF = lon(nlon-1)
>  Res1 at mpCenterLatF           = 90 - north_pole_lat
>  Res1 at mpCenterLonF           = 180 + north_pole_lon
>
> However I get this result ( I believe this is Australia):
>
>
> After several attempts I was able to plot the data using as bounds the
> “real” coordinates of the rotated projection, without specifying the
> center, e.g. :
>
>  Res1 at tfDoNDCOverlay=True
>  Res1 at mpLimitMode = "Corners"
>  Res1 at mpLeftCornerLatF = 30.35458
>  Res1 at mpLeftCornerLonF = -75.14440
>  Res1 at mpRightCornerLatF = 65.1125
>  Res1 at mpRightCornerLonF = 13.87071
>
> But the contour plot is still slightly shifted to the west as you can see
> in this image:
>
>
> I know that in the data file my coordinates span from rlon={340,392.875}
> and rlat={-9.962499,22.512501}.
>
> What am I missing?
> Is there any additional documentation on rotated grid?
>
> Attached is my NCL script (data are too big).
>
>
>
> Guido Cioni
> http://guidocioni.altervista.org
>
>
>
>
>
> _______________________________________________
> ncl-talk mailing list
> ncl-talk at ucar.edu
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20151130/49cbeaa8/attachment.html