LUT(3) User Contributed Perl Documentation LUT(3)NAMEPDL::Graphics::LUT - provides access to a number of look-up tables
SYNOPSIS
use PDL::Graphics::PGPLOT;
use PDL::Graphics::LUT;
# what tables are available
my @tables = lut_names();
# get the reversed colour table 'smooth',
# with the gamma intensity ramp
my ( $l, $r, $g, $b ) = lut_data( 'smooth', 1, 'gamma' );
# use the table idl5 in ctab
ctab( lut_data('idl5') );
DESCRIPTIONPDL::Graphics::LUT contains a number of colour look-up tables (in rgb
format) and intensity ramps, and provides routines to access this data.
The format of the data is suitable for use by "ctab" in
PDL::Graphics::PGPLOT.
Unlike the initial release of the package, the data tables are now
stored within the PDL distribution as FITS files (see $tabledir and
$rampdir), rather than in the module itself. Changes to these
directories will be picked up on the next call to one of the package
functions.
FUNCTIONSlut_names()
Return, as a list, the names of the available colour tables.
@tables = lut_names();
lut_ramps()
Return, as a list, the names of the available intensity ramps.
@ramps = lut_ramps();
lut_data()
Load in the requested colour table and intensity ramp.
( $l, $r, $g, $b ) = lut_data( $table, [ $reverse, [ $ramp ] ] );
Returns the levels and r, g, b components of the colour table $table.
If $reverse is 1 (defaults to 0 if not supplied), then the r, g, and b
components are reversed before being returned. If not supplied, $ramp
defaults to "ramp" (this is a linear intensity ramp).
The returned values are piddles containing values in the range 0 to 1
inclusive, and are floats.
VARIABLES
$tabledir
The directory in which the colour tables (in rgb format) are stored.
$rampdir
The directory in which the intensity ramps are stored.
$suffix
The suffix for the data files in $tabledir and $rampdir.
FURTHER INFORMATION
The colour tables were taken from the STARLINK GAIA package, and are
provided under the GNU copyleft. See http://star-www.rl.ac.uk/ and
http://star-www.dur.ac.uk/~pdraper/ for more details.
AUTHOR
Doug Burke (djburke@cpan.org), with thanks to Peter Draper/STARLINK for
providing the colour-table data, and Christian Soeller and Karl
Glazebrook for their help.
All rights reserved. There is no warranty. You are allowed to
redistribute this software / documentation under certain conditions.
For details, see the file COPYING in the PDL distribution. If this file
is separated from the PDL distribution, the copyright notice should be
included in the file.
perl v5.10.0 2003-11-17 LUT(3)
