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You can use IDL on the Linux desktops in the Astronomy group, where it is preinstalled, or you can obtain a copy for use offline, on another machine. Most of the instructions below are to do with the first case, but there are notes on the second case at the bottom.

To set up your machine for using SolarSoft-inflected IDL (works only on selected machines within Astronomy), there is some additional setup you need, beyond login, ssh and using unix.

Key points:

Setting up .cshrc §

Download the skeleton .cshrc file and save it as the file .cshrc in your home directory. You can do that a couple of ways.

At the command-line, type

% curl https://it.physics.gla.ac.uk/notes/applications/idl/idl.cshrc.txt >.cshrc

(where the % represents the shell prompt).

Or else it might be easier to click on the above link, copy the text of the file, and

% cat >.cshrc
<paste the file in place>

(where the ^D represents holding down the control key and typing d). Or do something similar with your favourite editor.

If you type ls after this, you won't see the file. If you type ls -a, however, you should see the file .cshrc amongst the listed files (the ls command, without options such as -a, suppresses display of files starting with a dot).

If you look at the newly-created .cshrc file (less .cshrc, then press space to look through the file, and q to quit), you will see a sequence of tcsh commands.

Over time, you will probably end up making substantial configuration adjustments to this .cshrc file, to point to data, catalogues, and cache locations, or to add convenient shortcut commands. Ask your predecessor PhD students for advice. To begin with, leave the file unchanged.

If you are aware of any errors in this skeleton file, or wish to suggest any additions, raise a ticket FAO Norman or Sandy.

Getting going §

If you are not already running Csh (type echo $0 to see your current shell) then type tcsh (not csh), and then:

% gossw
% sswidl

Local IDL: downloads and licences §

You can download the software for local installation from login.astro.gla.ac.uk or other group machines, in the directory /opt/idl/media/9.0. Thus from a macOS device, for example,

% scp login.astro.gla.ac.uk:/opt/idl/media/9.0/idl90-mac-x86_64.pkg .

and then install the package. Note that there are now x86_64 and arm install bundles now. If you're using a M1+ MacOS device, use the arm installer.

Licensing wrinkles:

  1. As of summer 2024 only versions 8.9 onwards of IDL can now be licenced, therefore if you are running an older version, please obtain the latest from the location noted above.
  2. You may need to license a copy of IDL to use on a laptop for use away from the Kelvin Building.

For assistance in either of these cases, consult CoSE IT.