[GEMPAK #VJX-948676]: GEMPAK: Extent distances in AREA with +++ + +

> When working with gempak point files and defining "area" in sf* programs,
> what/how are the distances used for the area parameter extents of +, ++,
> +++, etc?

Stephen,
The area boundaries are computed in lcabnd.f where the number of "+" or "-"
characters are used to create a zoom power of 2.

> 
> Which program(s) is used to determine the inclusion or exclusion of data at
> each level?

Data is included according to the FILTER setting (for graphic programs) if it 
is within the
specified area. If the "@" sign is used for data at specific stations, 
countries,
then that further restricts the data set. Otherwise, it is simply dependent on 
the lat/lon extents
calculated from the defined geographic region in $GEMTBL/stns/geog.tbl.

Steve Chiswell
Unidata User Support


> 
> I could not find any information in the GEMBUD or GEMPAK support archives.
> 
> Stephen Sinnis
> Pelmorex Media Inc
> T. 905.829.1159 x1379
> F. 905.829.5800
> 
> 


Ticket Details
===================
Ticket ID: VJX-948676
Department: Support GEMPAK
Priority: Normal
Status: Closed