Hi Denis,
I'd also done a "bit" of work on this, but I'll happily abandon my
efforts if your driver is now in the distribution.
I had a look at your code (haven't compiled it yet) but one thing I had
in my driver that you might like to consider adding is a check to see if
the file is CF compliant (or rather, a check to see if it has the CF
"Conventions" attribute).
Also, if I remember rightly (it's been a few months since I wrote it)
this check should stop your netCDF driver picking up "GMT" grid files,
which should be left to the GMT driver to deal with.
This is the check I added, with a bit of the existing code for reference:
/* -------------------------------------------------------------------- */
/* Try opening the dataset. */
/* -------------------------------------------------------------------- */
int cdfid, dim_count, var_count;
if( nc_open( poOpenInfo->pszFilename, NC_NOWRITE, &cdfid ) != NC_NOERR )
return NULL;
/*
----------------------------------------------------------------------- */
/*This bit added by Dominic Lowe, British Atmospheric Data Centre.*/
/*Checking for CF (Climate & Forecast) compliance:
First check for Conventions global attribute*/
/*
----------------------------------------------------------------------- */
attname = (char *) malloc(NC_MAX_NAME*sizeof(char));
if ((status = nc_get_att_text(cdfid, NC_GLOBAL, "Conventions",
attname)) != NC_NOERR)
{
CPLError( CE_Warning, CPLE_AppDefined, "No Conventions global
attribute");*/
/* note that 'Conventions' is always capital 'C' in CF spec*/
return NULL;
nc_close( cdfid );
}
/*then check Conventions is of the form "CF-etc" eg "CF-1.0"*/
if( attname[0] != 'C'
|| attname[1] != 'F'
|| attname[2] != '-' )
{
CPLError( CE_Warning, CPLE_AppDefined, "Convention attribute did
not match CF convention");
return NULL;
nc_close( cdfid );
}
/*
----------------------------------------------------------------------- */
Hope that's useful, I'll give the driver a go sometime soon.
Dominic
Denis Nadeau wrote:
GDAL now supports netcdf format using CF convention as specified by
unidata.
http://www.unidata.ucar.edu/software/netcdf/conventions.hdf
The software looks if the variables lat/latitude and lon/longitude are
presents in the netcdf file. If found, these variables are used to
specify the georeferencing transformation.
I'd like the community to try it out and if there are some problems,
let me know. GDAL netcdf format also works on Windows with he
precompile library version 3.6.1-beta1 (January 2005).
Regards,
Denis Nadeau
