gdl(1)
NAME
gdl - GNU Data Language incremental compiler
SYNOPSIS
gdl [--help] [-h] [--version] [-v] [-V] [[-]-quiet] [-q] [ -arg value ] [ -args ... ] [ -e statement ] [ -pref=/path/to/preferenceFile ] [ batch_file ... ]
DESCRIPTION
gdl is an incremental compiler for the GNU Data Language (GDL). GDL is being developed with the aim of providing an open-source drop-in replacement for ITTVIS Interactive Data Language (IDL). It is also partially compatible with Visual Numerics (VN) PV-WAVE. IDL and PV-WAVE are registered trademarks of ITTVIS and VN, respectively. GDL and its library routines are designed as a tool for numerical data analysis and visualisation. GDL is dynamically typed, vectorized and has object-oriented programming capabilities. The library routines handle numerical calculations, data visualisation, signal/image processing, file input/output (incl. graphical and scientific data formats such as TIFF, PNG, netCDF, HDF etc) and interaction with host OS. Information on GDL/IDL/PV-WAVE syntax and library routines can be found in e.g.: - GDL documentation draft at: http://gnudatalanguage.sf.net/gdl.pdf - IDL manual on-line @ NASA.gov: http://idlastro.gsfc.nasa.gov/idl_html_help/home.html - ITTVIS (ittvis.com) and Visual Numerics (vni.com) websites - comp.lang.idl-pvwave newsgroup A vast part of GDL library routines is implemented using open-source libraries including GSL, plPlot, and optionally: readline, FFTW, ImageMagick, netCDF, HDF4, HDF5, libproj4, UDUNITS-2, libps and others.
OPTIONS
--help (or -h)
Show summary of options
--version (or -v, -V)
Show version of program
--quiet (or -quiet, -q)
Suppress welcome messages
-arg value
Tells COMMAND_LINE_ARGS() to report the following argument (may
be specified more than once)
-args ...
Tells COMMAND_LINE_ARGS() to report all following arguments
-e statement
Execute given statement and exit (last occurrence taken into
account only, executed after startup file, may not be specified
together with batch files)
-pref=/path/to/PreferenceFile
(only partially working now) setting using external text file
few variables including default preferences (e.g. X11 Windows
Size)
--fakerelease version
setting !VERSION.RELASE to that value. !VERSION.RELASE is often
tested by procedures to decide whether some function or option
should be used. It is sometimes possible to use this option to
fool a procedure that request a specific value of
!VERSION.RELEASE
The -demo, -em, -novm, -queue, -rt, -ulicense and -vm options
are ignored for compatibility with IDL.
A list of batch files to be executed before entering the interactive
mode (but after executing a startup file, if specified) may be
given when not using the -e option.
FILES
$DATADIR/gnudatalanguage/lib/*.pro
Library routines implemented in GDL. $DATADIR is specified
during compilation and usually translates to /usr/share,
/usr/local/share or alike. GDL includes this directory in its
search path unless GDL_PATH or IDL_PATH env. variables are set
(see below).
$HOME/.gdl/history
A file used for storing the history of commands issued in the
interactive mode
ENVIRONMENT
The following environment variables have special meaning to gdl. The
GDL_* variant, if defined, takes precedence over any corresponding
IDL_* variant.
GDL_PATH, IDL_PATH
The GDL command (script) search path.
GDL_STARTUP, IDL_STARTUP
A file of commands to be executed on startup.
GDL_TMPDIR, IDL_TMPDIR
A directory in which temporary files may be created.
HOME, SHELL
Variables influencing shell invocations from within GDL (SPAWN
procedure and the $ interpreter command). Value of HOME
determines as well the location of the GDL history-file.
PATH Determines search path when spawning child processes using the
SPAWN procedure with the /NOSHELL keyword set.
PYTHONPATH
Influences behaviour of PYTHON procedure and PYTHON() function
(available if GDL is compiled with support for calling Python
code)
GDL_MPI
A message to be sent out using MPI_Send before initialization of
the interpreter (available if GDL is compiled with support for
MPI)
DISPLAY, XENVIRONMENT
Tell GDL how to connect to the X server
PLPLOT_DRV_DIR
Override the default location of PLplot dynamic drivers.
LC_* The locale-related settings accessible via LOCALE_GET() (GDL
always uses the C locale internally)
GDL_GR_WIN_HEIGHT
Sets the preference for the default height of a Windows(tm)
graphic window
GDL_GR_WIN_QSCREEN
if set to true (1) this will prevent the use of the
GDL_GR_WIN_HEIGHT and GDL_GR_WIN_WIDTH preferences and the
default dimensions of graphic windows will be 1/4 of the screen
dimensions
GDL_GR_WIN_WIDTH
Sets the preference for the default width of a Windows(tm)
graphic window
GDL_GR_X_HEIGHT
Sets the preference for the default height of an X11 graphic
window
GDL_GR_X_QSCREEN
if set to true (1) this will prevent the use of the
GDL_GR_X_HEIGHT and GDL_GR_X_WIDTH preferences and the default
dimensions of graphic windows will be 1/4 of the screen
dimensions
GDL_GR_X_WIDTH
Sets the preference for the default width of an X11 graphic
window
GDL_WX_BACKEND
can be set to [0,1,2] which will select, respectively, the
backends 0,1 or 2 of plplot's old wxWidgets driver (plplot
versions < 5.10). Backend 2 has antialiasing enabled.
GSHHS_DATA_DIR
If not automatically found, tells GDL where the gshhs files
(coasts rivers, etc) are located.
BUGS
Please report bugs, comments, patches or feature requests at http://sf.net/projects/gnudatalanguage/
AUTHOR
The primary author of GDL is Marc Schellens <m_schellens@users.sourceforge.net>. A list of contributors is available in the AUTHORS file shipped with GDL, and on the project website (see above). The original version of this manual page was written by Sergio Gelato <Sergio.Gelato@astro.su.se>. It is currently a part of the GDL package, and is maintained by the GDL Team.
SEE ALSO
netcdf(3), hdf(1), gsl(3)
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