arbitrary script means that it can be a shell script (on Windows this would be a batch file), a Python script or a script in any other language (e.g. PHP).

You can e.g. read some sensor value using e.g. a Python script and then pass the value to the control algorithm. Or you can have some control algorithm in REXYGEN and pass its output to a script which will execute the necessary actions.

It is also possible to combine this approach with use of REST API - for more details see: User manual REST API of REXYGEN

If you require more information, do not hesitate to contact me.

Regards, Tomas

Could you tell me what is "Arbitrary script executable on the Raspberry Pi