Ubuntu Manpage: gdl - GNU Data Language incremental compiler

Provided by: gnudatalanguage_1.0.1-3build1_amd64

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 Interactive Data Language (IDL) (RSI then ITTVIS then
Exelis and now Harris Geospatial Solutions, Inc.). It is also partially compatible with Visual Numerics
(VN) PV-WAVE. IDL and PV-WAVE are registered trademarks of L3Harris 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://aramis.obspm.fr/~coulais/GDL/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

- newsletter at: https://sympa.obspm.fr/wws/info/gdl-announces

A vast part of GDL library routines is implemented using open-source libraries including GSL, plPlot, and
optionally: readline, FFTW, Eigen3, ImageMagick, netCDF, HDF4, HDF5, PROJ, 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 (e.g. atv.pro)

--fussy
signals that all used procedures will adhere with modern IDL, where "()" are for functions and
"[]" are for arrays. This speeds up (sometimes terribly) compilation but choke on every use of
"()" with arrays. Conversion of procedures to modern IDL can be done with D. Landsman's
idlv4_to_v5 procedure. Use enviromnment variable "GDL_IS_FUSSY" to set up permanently this
feature.

Incidentally "being fussy" can help find all places in a procedure that need to be corrected to
have it in the modern IDL format.

--sloppy
inverse of fussy above. Sets the traditional (default) compiling option where "()" can be used
both with functions and arrays. Needed to counteract temporarily the effect of the enviromnment
variable "GDL_IS_FUSSY".

--use-wx
Tells GDL to use WxWidgets graphics instead of X11 or Windows. (nicer plots). Also enabled by
setting the environment variable GDL_USE_WX to a non-null value.

--no-use-wx
Tells GDL no to use WxWidgets graphics, even if env. var. "GDL_USE_WX" is set.

--no-dSFMT
Tells GDL not to use double precision SIMD oriented Fast Mersenne Twister(dSFMT) for random
values. Also disabled by setting the environment variable GDL_NO_DSFMT to a non-null value.

With dSFMT, although the Mersenne Twister algorithm is the same as in modern IDL, the values are
computed in parallel (hence a speed gain) but the output order is not the same as IDL. Also, the
seed is different. Theses differences should not be a problem as it is discouraged to interfere
with seed values.

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 (if GDL compiled
              within ReadLine)

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.

       GDL_MAPS_DIR
              If not automatically found,  tells  GDL  where  the  maps  files  (coasts  rivers,  etc,  used  by
              MAPS_CONTINENTS)  are  located.   These are in Shapefile format and newer versions can possibly be
              present on naturalearthdata.com

BUGS

       Please report bugs, comments, patches or feature requests at https://github.com/gnudatalanguage/gdl/

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.