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[IDV #FAY-719487]: Albers Conical Equal Area netCDF

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  • Subject: [IDV #FAY-719487]: Albers Conical Equal Area netCDF
  • Date: Wed, 05 Mar 2008 08:08:26 -0700
Hi Tyn-

> Full Name: Valentijn Venus
> Email Address: address@hidden
> Organization: ITC
> Package Version: 2.5b1 build date:2008-03-02 08:05 UTC
> Operating System: Linux
> Hardware: Java: home: /usr/lib/jvm/ia32-java-6-sun-1.6.0.03/jre version: 
> 1.6.0_03 j3d:1.3.1
> Description of problem: Hi-
> 
> i'm trying to enhance a netCDF file with NDVI data over Africa, which is 
> projected in
> Albers Equal Area. According the netCDF 2.22 API, this projection should be 
> supported
> but i'm iunsure how to enhance thsi netCDF for IDV to load it:
> 
> <?xml version="1.0" encoding="UTF-8"?>
> <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2"; 
> location="dods://iridl.ldeo.columbia.edu/SOURCES/.USGS/.ADDS/.NDVI/.NDVIrg/.dekadal/.maximum/.NDVI/dods"
>  >
> <attribute name="title" type="String" value="ETOPO2 Global 2' Elevations" />
> <variable name="projection_x_coordinate" shape="x" type="float">
> <attribute name="units" type="String" value="meters" />
> </variable>
> <variable name="projection_y_coordinate" shape="y" type="float">
> <attribute name="units" type="String" value="meters" />
> </variable>
> <variable name="NDVI" shape="T y x" type="double">
> <attribute name="long_name" type="String" value="normalized difference 
> vegetation index" />
> </variable>
> </netcdf>

You'd need something like the following:

   char Albers_Projection;
     :grid_mapping_name = "albers_conical_equal_area";
     :standard_parallel = 20.0, 60.0; 
     :longitude_of_central_meridian = -32.0; 
     :latitude_of_projection_origin = 40.0; 
     :false_easting = 0.0;
     :false_northing = 0.0;
     :_CoordinateTransformType = "Projection";
     :_CoordinateAxisTypes = "GeoX GeoY";

and for projection_x_coordinate and projection_y_coordinate, you'd need to add:


<attribute name="_CoordinateAxisType" type="String" value="GeoX" />

<attribute name="_CoordinateAxisType" type="String" value="GeoY" />

respectively.

Don


Ticket Details
===================
Ticket ID: FAY-719487
Department: Support IDV
Priority: Normal
Status: Open