[mapserver-users] Netcdf / WCS

[Frank Warmerdam]

vincent wrote:
> Hello,
> 
> I would like to create Web Coverage Service from one netCDF file in 
> following http://mapserver.gis.umn.edu/docs/howto/WCSServerFormatHowTo
> 
> My netCDF store rainfall matrix every five minutes in the "pluie" 
> variable. This the CDL :
> 
> dimensions:
> 
>    time = UNLIMITED;   // (496 currently)   // (has coord.var)
>    x = 50;   // (has coord.var)
>    y = 50;   // (has coord.var)
> variables:
>    int Lambert_Conformal;
>      :grid_mapping_name = "lambert_conformal_conic";
>      :standard_parallel = 43.20317, 44.99683; // double
>      :longitude_of_central_meridian = 2.337229; // double
>      :latitude_of_projection_origin = 44.1; // double
>      :false_easting = 600.0; // double
>      :false_northing = 3200.0; // double
>      :_CoordinateTransformType = "Projection";
>      :_CoordinateSystems = "ProjectionCoordinateSystem";
>      :_CoordinateAxes = "y x";
>      :_CoordinateAxisTypes = "GeoX GeoY";
> *   double pluie(time=496, y=50, x=50);*
> *     :units = "mm/h";*
> *     :long_name = "Intensité de pluie";*
> *     :coordinates = "lat lon";*
> *     :grid_mapping = "Lambert_Conformal";*
> *     :_CoordinateSystems = "ProjectionCoordinateSystem LatLonCoordinateSystem";*

Vincent,

Because GDAL treats this array as a single dataset having 496 bands, I don't
believe there is a way to properly create a tileindex with one entry per
time slice, referring back directly to that band though this is something that
I think was discussed at one point.

You *can* serve the pluie array, but it will be represented as having 496
bands along a dimension called Band instead of time.

Hopefully Steve will correct me if I am wrong.  What would be nice
is a way to have WCS (and raster rendering in general) potentially
override the BANDS= processing option with information read from a
tile index, and then update the gdaltindex program accordingly to
generate such results.  This shouldn't - in theory - be too hard to
implement.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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