LC Hotline: 2-4531

From offsite: (925) 422-4531



8am–12pm, 1–4:45pm
B453 R1103 | Q-clearance area




IDL (Interactive Data Language) is a product from ITT Visual Informations Systems (ITTvis). IDL enables in-depth data analysis through industry-leading visualization. This easy-to-learn, cross-platform, application development software is relied on by analysts and engineers around the globe. IDL's interactive, high-level language can help you make discoveries and display your solution.

IDL at LLNL includes four licenses for the Advanced Math and Statistics (AMS) package, two on the OCF and two on the SCF networks. Note that IDL for Mac OS X does not support AMS or ISML.


Machines and Versions

See LC graphics software page.


/usr/local/tools/idl. Links to the latest version exist in /usr/local/bin.


To setup your PATH and any other needed environment variables, type use idl.

Coyote and Catalyst Libs

When you run idl or idlde on LC machines, you will also get the Coyote and Catalyst libraries added to your IDL_PATH. See the Coyote web page for details.


IDL for UNIX can be used with one of two different interfaces. Starting IDL with the idl command begins a traditional IDL session using a simple text command line interface. If you are running the X window system, IDL can also be started with the idlde command, which invokes a convenient multiple-document interface called the IDL Development Environment.

To use the Advanced Math and Statistics (AMS) routines that are available with IDL Analyst, start up IDL in the manner shown above. Calling one of the IDL AMS routines will cause an IDL Analyst license to be checked out to you until you quit IDL. LC has 2 licenses for AMS on the OCF and two on the SCF.

Play nice with licenses!

1) Please do not hold onto IDL licenses overnight ("hoarding") unless you are actually using them -- hoarding licenses creates artificial scarcity and encourages further hoarding by others. It's a vicious circle.

2) If you are using multiple licenses, and we run out of licenses, please consider releasing one or two so that we are not out any more.

How to get "extra" "free" licenses: An important quirk of IDL licensing is that IDL checks out only one license (six tokens) per node/DISPLAY, no matter how many instances of IDL you run on that node. This can be confirmed easily by running them by hand and checking the license server records. So if you get 16 CPUs on one node, each with 4 cores, you might be able to make good use of as many as 64 copies of IDL using only a single license! Please ask for more details.

Older Versions: Older versions are available using dotkit. To run an older version, type use idl-version where version is the version number with no spaces or periods (e.g. 82 for version 8.2). See the graphics software matrix for a list of the versions available on the machines. Another way to check is to use dotkit's tab completion feature: type use and hit the tab key twice quickly and wait for dotkit to show you the versions. Once you issue the "use" command, your PATH will be set to get the version you specify. For more information about dotkit, call the LC Hotline at 422-4531.


From the IDL command language prompt, you can get online help by typing a question mark.

At the UNIX shell prompt, the following commands are available:

Online help:


IDL Online Guide:


IDL demonstration:


A very good archive of Technical Tips is available on the Technical Articles Archive. Online seminars and more are available from the ITTvis Technical Support page.

Coyote's Guide to IDL Programming is an excellent resource for people who want to learn more about IDL.

Help is available from the, (925) 422-4531.


You can install IDL on your local workstation. IDL and installation instructions can be downloaded from You will need to create a free web account on IDL's website to download the software. Click on the "My Account" button in the upper right of their website to create or access your account. Once you have logged into their web page and clicked "My Account," you will see a download link in the middle of the page. Select "IDL" from the "Select Your Product" popup, then choose the Full Install package for your platform. The software is available for Linux, Mac and Windows. The IDL Analyst and IMSL libraries are not available on OS X as of July 2012.

If you have an account on the LC platforms, you can use the LLNL LC site license to process data generated on Livermore Computing resources. To access the LC license, the LC IDL license file must be placed on your local machine. The license file can be copied from /usr/global/tools/licservers/idl/idl.lic on any LC machine where IDL is installed. If you do not have an LC account, then please contact the hotline to obtain one. Once you have downloaded this file, you can simply place it into the license subdirectory of the ITT installation and rename it to license.dat. On a Windows machine, the license directory is typically C:\Program Files\ITT\license.

Alternatively, you can tell IDL about the LC license during installation. Download the license file to your desktop, then rename the LC license file to something ending with ".dat" or ".lic" and tell the License Wizard where the file is. The License Wizard runs during installation and can be found in the IDL installation directory after install. This is (idl81/bin/ittlicense for Linux/Mac, or on Windows, Start Menu --> All Programs --> IDLx.x --> License Wizard to activate the license. In the License Wizard, choose "install license you have received" and navigate to your downloaded and renamed license file.