The following functions can be used only for defining custom Activation Actions - they mostly deal with causing something to happen, such as popping up an image display window. They generally return a short string, which will be logged to the user to give an indication of what happened (or didn't happen, or should have happened). The documentation in the following subsections is also available from within TOPCAT in the Available Functions Window.
Some of these items offer rather out of date functionality. They may be withdrawn (replaced by better alternatives) in future releases.