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[IDV #PKC-150970]: Question about 0-360 grids versus -180-to-+180 grids

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  • Subject: [IDV #PKC-150970]: Question about 0-360 grids versus -180-to-+180 grids
  • Date: Tue, 02 Sep 2014 11:30:48 -0600
Murray,

Question. What projection are you using for your data? If you are using a
lat/lon projection there may be a workaround. In particular, there is a grid
diagnostic formula called "lonflip" that may offer a solution. From the
documentation:

"Flip the longitudes in a grid from -180-180 to 0-360 (or vice-versa). Only
works for cyclic rectilinear grids."

Best,

Unidata IDV Support

> This is very good news.  There is an equivalent "tool" in Saga GIS that works 
> well, and their code is public domain.  Are you interested?
> 
> 
> -----Original Message-----
> From: Unidata IDV Support [mailto:address@hidden]
> Sent: Tuesday, September 02, 2014 12:05 PM
> To: address@hidden
> Cc: address@hidden
> Subject: [IDV #PKC-150970]: Question about 0-360 grids versus -180-to-+180 
> grids
> 
> Murray,
> 
> We are in the planning stages here at Unidata to resolve this issue. 
> Unfortunately, it requires "deep surgery" and will take time to resolve so we 
> do not have an immediate solution for this problem at this time. But it will 
> get fixed eventually.
> 
> Best,
> 
> Unidata IDV Support
> 
> > Folks,
> >
> > I have a grib2 file that runs from 0-360, and it's no problem to
> > display or subset any areas that fit within this frame.  But I'd like
> > to display a grid over all of Africa, and that would cross the
> > 360-degree right side.  Is there a control or function that splits the
> > 0-360 grid and combines the halves into a -180-to-+180 map?  Or any 
> > equivalent trick I don't know about?
> >
> > Murray
> 
> Ticket Details
> ===================
> Ticket ID: PKC-150970
> Department: Support IDV
> Priority: Normal
> Status: Open
> 
> 


Ticket Details
===================
Ticket ID: PKC-150970
Department: Support IDV
Priority: Normal
Status: Closed