IDL on the Web

Part of the Practical IDL Programming Web

Many valuable resources are available online for IDL programmers. A few minutes spent searching the web will often yield source code  for a particular application or advice on how to solve a problem. Good programmers know when to write new code, but great programmers know when to use someone else's code.

General information

The RSI web site provides product information about IDL (e.g., current supported platforms), as well as marketing and technical support information. Installable versions of IDL may be downloaded from the RSI anonymous FTP site. A particularly useful resource is the searchable database of IDL technical tips from the RSI support staff.

The Usenet newsgroup comp.lang.idl-pvwave is an active discussion forum for IDL programming issues, and is frequented by many expert IDL programmers who are willing to answer questions. You can also access the newsgroup via Google Groups.

The Astronomy Library includes thousands of IDL procedures and functions developed by the astronomical community. This site also offers a searchable index and a comprehensive list of links to other IDL-related web sites and project specific IDL libraries, including a library for reading and writing data in the Flexible Image Transport System (FITS) format.

The Applied Physics Laboratory Library at Johns Hopkins University is a comprehensive general purpose IDL library containing over 600 procedures and functions.

The Searchable Library Database created by Eric Deutsch at the University of Washington provides a searchable index of just about every publicly available IDL procedure or function. Type a routine name or a topic keyword and a list of all matching procedures and functions will be returned, along with a link to the source for each routine.

Development tools

The IDL Emacs mode provides a customized environment for editing and running IDL applications.

Nedit is a freely available point-and-click text editor for all major UNIX platforms (including Linux).

BBEdit is a point-and-click text editor for MacOS platforms.

The Ghostview and GSView applications for Windows and UNIX may be used to view PostScript files created in IDL, and to create Encapsulated PostScript files with preview images.

On MacOS platforms, the MacGhostView application may be used to view PostScript files. To print PostScript files on MacOS platforms, try Drop*PS.


Many of the best IDL programmers maintain web sites that provide high quality IDL source code relevant to a range of disciplines.

Marc Buie provides a library of astronomy-related and general-purpose routines.

Matthew Craig developed the TeXtoIDL package, which allows equation formatting in IDL using a TeX-like syntax.

Eric Deutsch offers a collection of astronomy-related IDL routines.

J. D. Smith maintains the IDL Mode for Emacs.

David Fanning maintains a comprehensive IDL website that includes a collection of illustrative and useful IDL programs; a valuable list of IDL programming tips; information about his book IDL Programming Techniques, and many other useful resources.

Struan Gray has written an excellent tutorial on creating complex shaded surfaces in IDL.

Mark Hadfield provides a collection of procedures and functions with an emphasis on object oriented programming.

Eric Korpela has developed a memory-mapped extension for IDL on UNIX platforms that allows the use of very large arrays.

Craig Markwardt has implemented a robust set of generalized curve-fitting routines in IDL and also provides a useful set of array and graphics utilities.

Martin Schultz provides a collection of general-purpose IDL utilities, along with specialized applications for the analysis of geophysical data.

David Windt maintains a library of specialized optics routines along with a set of general-purpose routines.


If you don't have a copy of Practical IDL Programming handy, then do yourself a favor and buy one! In the meantime, you may find the following tutorials useful.

Boston University provides a useful introduction to IDL basics, as does NCSA.

Christophe Morisset has written a cookbook for beginners that includes an explanation of programming topics including IDL statements.

Elements of IDL is an introduction to IDL programming from the University of Colorado at Boulder in PostScript format.

Hugh Pumphrey provides a short course in IDL programming at the Meteorology Department at the Unversity of Edinburgh.

Institut d'Astrophysique Spatiale provides IDL programming and graphics tutorials in French.

Norbert Hahn provides an IDL handbook in German at the Universitat Gieben.

Liam E. Gumley (updated 2003/08/07)