Information Technology Services

IDL at Dartmouth


IDL (Interactive Data Language) is a complete computing environment for the interactive analysis and visualization of data. IDL integrates a powerful, array-oriented language with numerous mathematical analysis and graphical display techniques. Programming in IDL is a time-saving alternative to programming in FORTRAN or C. You can explore data interactively using IDL commands, then create complete applications by writing IDL programs.

Installation and Licensing

IDL may be downloaded locally, installed from DVD, or downloaded directly from Exelis. However, without a valid license, it will only operate in a seven-minute demo mode.

Linux and Macintosh workstations with an AFS client installed may directly run IDL from our central servers. No local installation is needed other than some symbolic links for convenience.

Dartmouth has a small number of floating licenses available. The network license file is available at the local download link. Single licenses are much more expensive than bulk licensing. Please contact [email protected] if you are considering purchasing a private license. Student licensing is also available.

Features of IDL

  • IDL is a complete, structured language that can be used both interactively and to create sophisticated functions, procedures, and applications.
  • Operators and functions work on entire arrays (without using loops), simplifying interactive analysis and reducing programming time.
  • Immediate compilation and execution of IDL commands provides instant feedback and "hands-on" interaction.
  • Rapid 2D plotting, multi-dimensional plotting, volume visualization, image display, and animation allow you to observe the results of your computations immediately.
  • Many numerical and statistical analysis routines, including Numerical Recipes routines, are provided for analysis and simulation of data.
  • IDL's flexible input/output facilities allow you to read any type of custom data format. Support is also provided for common image standards (including BMP, GIF, JPEG, and XWD) and scientific data formats (CDF, HDF, and NetCDF).
  • IDL widgets can be used to quickly create multi-platform graphical user interfaces to your IDL programs.
  • IDL programs run the same across all supported platforms (UNIX, VMS, Microsoft Windows, and Macintosh systems) with little or no modification. This application portability allows you to easily support a variety of computers.
  • Existing FORTRAN and C routines can be dynamically-linked into IDL to add specialized functionality. Alternatively, C and FORTRAN programs can call IDL routines as a subroutine library or display "engine."


The floating licenses are valid for all versions from 5.0 (possibly earlier) up to the current version. The versions installed in AFS and available to UNIX workstations and central systems are summarized in the table below. In general, the default version on any particular platform is the latest that can run on that platform. Other available versions can be run by appending the version number (e.g., idl71).

Local Documentation

The main IDL reference manuals are distributed as PDF files. They are available with each local installation, or from Exelis' web site. In addition, the idlhelp application has all of the reference material. Idlhelp does not require a license.

There is a local mailing list, [email protected], for dissemination of information on licensing, new version installs, bug reports, etc.

The list archives and subscription information are available on the Web; see Archives of [email protected]. All IDL users are encouraged to subscribe to this mailing list.

For more information, see:

Research Computing
Scientific and Research Software
Last updated: 
Monday, July 18, 2016

If you have questions or need further information, contact your department's IT support office, or contact the IT Service Desk via email at [email protected], via phone at 603-646-2999 or walk in to see them in Baker/Berry 178J.

Information Technology Services