Interactive Data Language (IDL) is both a high-level progamming environment and an interactive data- handling and visualization tool. IDL is available on several platforms including linux, MacOS and Windows. IDL is widely used in the astrophysics community, providing many software packages freely available for use. IDL is a product of Harris Geospatial Soulutions.

Using IDL


module load idl/8.8



source /Applications/harris/idl88/bin/idl_setup


You can also start idl with: /astro/local/bin/idl (as with previous versions)

The previous version of IDL is still available as idl873


With IDL 8.7 and above, the license regime of IDL has changed. There are now two types of licenses:

  1. Floating
  2. Node locked

You will normally use a floating license. To use a floating license you need to be on cabled UiO-network or run VPN. Some projects pay for node locked licenses for laptops that are frequently outside UiO. This is still possible (contact Torben). If you from time to time (for instance on travel) need an IDL license to work offline for a shorter period, you can borrow a time limited license (up to 60 days) from the license server. More on how to do this here.

Installing IDL on your MacOS laptop

First dowload and install idl882-mac.pkg

then download and install idl_8.8.2_astro_laptop.pkg

If you run into trouble when installing on MacOS 10.15, read this first.

After installation, the IDL start scripts for command line usage will be located in /usr/local/bin. You can also use the IDL development GUI by starting the IDL app in /Applications/harris/idl/.


Read this if you have a Mac laptop with M1 processor

Read this if you have problems with X windows hanging on MacOS 10.15 and above

More trouble shooting articles

IDL 8.8.2 Documentation

What's new in IDL 8.8.2

IDL documentation center

IDL Programming

IDL reference

IDL libraries

IDL Advanced Math and Stats

The IDL Machine Learning Framework

IDL Graphics Examples

Using IDL (pdf)

IDL Image Processing (pdf)

IDL DataMiner Guide (pdf)



Older versions of IDL


    By Torben Leifsen
    Published July 5, 2011 11:45 AM - Last modified Apr. 16, 2022 5:17 PM