[Scilab-users] calculate TRMS value in Xcos

[Sachverständigenbüro Niedermaier Holger]

Dear all, 
by simulating an electrical power circuit I’d like to plot the voltage and the current over time, which is easy to perform by using the scope block. 
In addition to the signal recorded I’d like to calculate the TRMS value of the plotted current and voltage signal. 
Unfortunately Xcos does not include a TRMS block like e.g. Simulink do. 
Because I’m so far not so familiar with Xcos and Scilab I’d like to ask the community for support. 
Does anybody have a good idea or advise how to get the TRMS value of the recorded signal?
Thanks and nice weekend
Holger