LUT(3) User Contributed Perl Documentation LUT(3)
PDL::Graphics::LUT - provides access to a number of look-up tables
# 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') );
PDL::Graphics::LUT contains a number of colour look-up tables (in rgb format) and inten-
sity 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
Return, as a list, the names of the available colour tables.
@tables = lut_names();
Return, as a list, the names of the available intensity ramps.
@ramps = lut_ramps();
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
The directory in which the colour tables (in rgb format) are stored.
The directory in which the intensity ramps are stored.
The suffix for the data files in $tabledir and $rampdir.
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
Doug Burke (firstname.lastname@example.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 dis-
tribution. If this file is separated from the PDL distribution, the copyright notice
should be included in the file.
perl v5.8.0 2002-04-24 LUT(3)