"Writing a Plugin Model" does not explain function "random"

[Joachim Wuttke]

Each SasView? seems to contain a function "random", on a par with "Iq".

However, I find no explanation of this function on the otherwise well
written and informative page "Writing a Plugin Model" [1].

Could you please point me to an existing explanation of "random", or
briefly improvise such explanation?

Thanks, Joachim

[1] ​http://www.sasview.org/docs/user/sasgui/perspectives/fitting/plugin.html