Re: [netcdf-java] subset GeoGrid problem

• To: John Caron <caron@xxxxxxxxxxxxxxxx>
• Subject: Re: [netcdf-java] subset GeoGrid problem
• From: Sachin Kumar Bhate <skbhate@xxxxxxxxxxxxxxx>
• Date: Tue, 24 Feb 2009 09:11:37 -0500

John Caron wrote:

Hi Sachin:

Im not sure why you are  casting to GridCoordSys. The following is the correct 
way to use this:

    GridCoordSystem gcsi = grid.getCoordinateSystem();
    boolean vAxis = (gcsi.getVerticalAxis() != null);

Ah! ..nice tip from the master. :-)

is there some functionality you need from GridCoordSys that you cant get from 
GridCoordSystem
interface ?

But, I think I can implement that in a better way...

thanks..appreciate your quick input

Sachin

Sachin Kumar Bhate wrote:

John,

I had earlier reported the problem described below with nj2.2.22.
The same problem still exist in netcdf-java 4.0 as well.

My current testing netcdf-java version is

Version 4.0.34.20090220.0016
Build Date = 2009-02-20 00:16:36


-sachin

John Caron wrote:

hi sachin:

thanks for reporting, ill look into this.
which version of the library are you using?

Sachin Kumar Bhate wrote:

Hello,

I am trying to query a subsetted GeoGrid for 'vertical axis', and
it returns false when I know that the data has vertical axis.
The original grid does return 'true' for the presence of vertical axis,
so it looks like the flag (hAxis/pAxis/zAxis) is not getting set after
subsetting the GeoGrid.

Just wanted to report this as this method has been a loyal gatekeeper
for me when I am trying to get vertical coordinate data when there is
none.

 >>>
example code:

String uri='http://www.gri.msstate.edu/rsearch_data/nopp/bora_feb.nc';
String var='temp';

GridDataset gid = GridDataset.open(uri);
GeoGrid Grid = gid.findGridByName(var);
GridCoordSys gcs = (GridCoordSys) Grid.getCoordinateSystem();

boolean vAxis = gcs.hasVerticalAxis();          // returns true.

// subset geogrid
GeoGrid subg = Grid.subset(null,null,null,1,1,1);       GridCoordSys
gcs2 = (GridCoordSys) subg.getCoordinateSystem();

boolean vAxis2 = gcs2.hasVerticalAxis();   // returns false, should
return true.

<<<

thanks..

Sachin.

--
Sachin Kumar Bhate, Research Associate
MSU-High Performance Computing Collaboratory, NGI
John C. Stennis Space Center, MS 39529
http://www.northerngulfinstitute.org/

• References:
  • Re: [netcdf-java] subset GeoGrid problem
    • From: Sachin Kumar Bhate
  • Re: [netcdf-java] subset GeoGrid problem
    • From: John Caron