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[netCDFJava #HCW-753528]: GridCoordSystem. findXYindexFromLatLon()

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  • Subject: [netCDFJava #HCW-753528]: GridCoordSystem. findXYindexFromLatLon()
  • Date: Mon, 19 Jun 2017 17:29:49 -0600
Hi Nihat,

GridCoordSystem.findXYindexFromLatLon() returns a 2-element array, ret[0] for x 
index and ret[1] for y index. As you say, one index can be valid (>= 0) and one 
can be invalid (-1). Therefore, you shouldn't conclude that a given lat/lon is 
contained within the grid unless both indices are >0. I can see your point that 
it may be risky to convey the information that way, but sometimes it can be 
useful to know when a lat is valid and a lon is not, or vice versa.

If necessary, the lat/lon is converted into projection coordinates of the grid. 
Apart from that, there is no interpolation.

The documentation for the method isn't as detailed as it could be, but you can 
follow the code to see what's happening. It's not too complex. The latest 
source for NetCDF-Java 4.6 can be found on the master branch of our GitHub repo 
[1].

Cheers,
Christian

[1] https://github.com/Unidata/thredds/tree/master

Ticket Details
===================
Ticket ID: HCW-753528
Department: Support netCDF Java
Priority: Normal
Status: Closed
===================
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