OMEdit: Simulation of Media.Examples.R134a produces Error

[anonymous]

When trying to compile and simulate the examples for the R134a lib in OMEdit, I get the following error (Ubuntu Linux 14.04, 64 Bit)

" Model error: Argument of log(adelta) was nan should be >0 "

I have tried to find the problem in the sources (R134a.mo), and it looks like the calculation of the absolute value of variable "delta" is not calculated correctly (abs()-function not working?)

[Rüdiger Franke]

The same error shows up in the nightly tests. One reason is that records are not constructed appropriately in functions. See the following example:

model RecordConstructor
  record R
    parameter Integer n = 3;
    Real[n] a = {1, 2, 3};
  end R;

  function f
    output Real y;
  protected
    R r;
  algorithm
    y := r.a[r.n];
  end f;

  model Test
    parameter R r;
    Real y_good = r.a[r.n];
    Real y_bad = f();
  end Test;
end RecordConstructor;

Saving it to RecordConstructor.mo and calling omc with:

loadFile("RecordConstructor.mo");
simulate(RecordConstructor.Test);
val(y_good, 1);
val(y_bad, 1);

gives

3.0
1.637325164314311e-306

This is a blocker because many Modelica models use data records and the consequences on the simulation are arbitrary.

[Adrian Pop]

Fixed in fd7495/OMCompiler