PDL::NetCDF, version 0.63

Allows reading and writing of NetCDF files into and out of PDL objects using
a simple object-oriented interface.  NetCDF is a flexible, binary, portable
file standard for storing gridded data.  One can access netCDF files through
interface libraries in FORTRAN, C/C++ and perl.  Numerous utilities also exist
for manipulating these files.

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NOTE:  This package *used* to be called PDL::NetCDFobj.  The *old* PDL::NetCDF
was a quick re-write of the NetCDF perl package available from unidata
(http://www.unidata.ucar.edu/packages/netcdf) to return PDLs instead of nested
perl lists.

This package is a new, higher-level, 
object-oriented interface to netCDF, which is more tightly integrated to PDL.
The old PDL::NetCDF is no longer supported.
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The following are required for installation:

-- PDL v2.0 or above 

If you want to use the old version of pdl (pdl 1.11), please
use PDL::NetCDF version 0.34, also available on CPAN.  

-- perl 5.004 (or later)
-- NetCDF version 3 or later

The first two are available on CPAN.  The third is available from UCAR UNIDATA 
at 

http://www.unidata.ucar.edu/packages/netcdf/index.html


SYNOPSIS:

use PDL;
use PDL::NetCDFobj;

my $ncobj = PDL::NetCDFobj->new ("test.nc");  # New file
my $pdl = pdl [[1, 2, 3], [4, 5, 6]];

# Specify variable name to put PDL in, plus names of the dimensions.  Dimension
# lengths are taken from the PDL, in this case, dim1 = 2 and dim2 = 3.      
$ncobj->put ('var1', ['dim1', 'dim2'], $pdl); 

my $pdlout = $ncobj->get ('var1'); # $pdlout = [[1, 2, 3], [4, 5, 6]]

# Store textual NetCDF arrays using perl strings:  (This is a bit primitive, but works)
my $str = "Station1  Station2  Station3  ";
$obj->puttext('textvar', ['n_station', 'n_string'], [3,10], $str);
my $outstr = $obj->gettext('textvar');
# $outstr = "Station1  Station2  Station3  "

my $dim1size = $ncobj->dimsize('dim1'); # $dim1size = 2

# A slice of the netCDF variable.
# [0,0] is the starting point, [1,2] is the count.
my $slice  = $ncobj->get ('var1', [0,0], [1,2]); # $slice = [1,2]

# Attach a double attribute of size 3 to var1
$ncobj->putatt (double([1,2,3]), 'double_attribute', 'var1');

my $attr1 = $ncobj->getatt ('double_attribute', 'var1'); # $attr1 = [1,2,3]

# Write a textual, global attribute.  'attr_name' is the attribute name.
$ncobj->putatt ('The text of the global attribute', 'attr_name');          

my $attr2 = $ncobj->getatt ('attr_name'); 
# $attr2 = 'The text of the global attribute'

# Close the netCDF file.  The file is also automatically closed in a DESTROY block
# when it passes out of scope.  This just makes is explicit.
$ncobj->close;


INSTALLATION:

Installation should be the normal:

perl Makefile.PL
make
make test

(as root)
make install

If you have problems, see the PROBLEMS file.

Best of luck!

Doug Hunt
dhunt@ucar.edu
Software Engineer III
UCAR - GPS/MET