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

Murray,

In the field selector, go to "Formulas" Data Sources.

Select Grids > "Define a grid diagnostic".

Select a Display of Color-Shaded Plan View or the display of your choice.

Click Create Display.

This action will bring forth an input window.

Enter the formula "lonflip(a)"

Click OK

Now select the relevant field in the pop-up "Field Selector" dialog.

Click OK.

These actions should result in the desired image.

Let us know if you have trouble.

Best,

Unidata IDV Support

> Please put an old man out of his misery, and tell him exactly where are the 
> grid diagnostic formulas.  Your tool sounds perfect, but I have no idea where 
> to look.
> 
> 
> -----Original Message-----
> From: Unidata IDV Support [mailto:address@hidden]
> Sent: Tuesday, September 02, 2014 1:31 PM
> To: address@hidden
> Cc: address@hidden
> Subject: [IDV #PKC-150970]: Question about 0-360 grids versus -180-to-+180 
> grids
> 
> 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
> 
> 


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