NumRPC is a lightweight Remote procedure call (RPC) mechanism for exchanging numbers between different processes.
A typical use case is the numerical simulation of physical systems which include some advanced control logic. The languages of choice for the simulation of physical systems are different from the ones well suited for advanced control (ex. Modelica for physical simulation vs. Python, Julia or Matlab for control). The RPC mechanism provides a bridge between the two languages to run a closed loop simulation of the physical system with its control.
In this context, the RPC mechanism is used in the following way:
- the RPC client (Modelica) is the numerical simulation of a physical system which needs some control (e.g. heating system of a building).
- the RPC server (Python, Julia or Matlab) provides the control logic for the physical system
Consequently, the Modelica simulation periodically sends a request to the server which carries the inputs for the control algorithm. The server runs the control algorithm and sends back the outputs.
NumRPC protocol is based on a request-response mechanism. The client sends to the server a request for a function to be executed on the server. The request message carries the function id plus a list of arguments for that function. The server answers back the list of outputs of that function.
In NumRPC, all arguments and outputs are floats
(double precison floating-point numbers, i.e. double in C, Real in Modelica)