Added functions for getting FMU metadata

[sathvikbhagavan]

Added functions for getting input, output, state, parameter and derivative names from FMU modelDescription.

[sharanry]

Can the tests check not just length of the result but the actually values of the results?

[ThummeTo]

Can the tests check not just length of the result but the actually values of the results?

In general, we want to accomplish that by implementing the FMI-CrossChecks from ModelicaAssoctation. This repo is currently archived and will be replaced by a successor soon, so it will still take some time.

As workaround, we are checking for simulation results/states at t=0 (everything initialized correctly?) and t=end (last simulation time step). This is not perfect, but chances are high that the simulation between worked correctly if t=end is not a stable equilibrium or similar of the system. And as said, it's only a workaround until we have the new cross-checks. So I would suggest to check at least results at simulation start and stop?

[ThummeTo]

BTW: @sathvikbhagavan much appreciated! Let me know when you are ready to review/test :-)

[sathvikbhagavan]

This PR involves the implementation of utility functions involving extracting things from modelDescription. I don't think there is any need to check the simulation. I think we are ready to review/test.

[ThummeTo]

Can the tests check not just length of the result but the actually values of the results?

Ah now I see what you meant, in fact you are right. The tests are only checking for the length of the name-arrays instead of checking their actual content. This is not good... I will fix this. And if it is ok @sathvikbhagavan I would rename the functions to better fit the tone of the FMI-command-set?

[sathvikbhagavan]

I added some tests for checking the values of the arrays yesterday. But if you think more tests are required, please feel free to add them. I am fine with renaming functions according to the FMI convention.

[ThummeTo]

@sathvikbhagavan I am on merging that, do you know fmi2ValueReferenceToString and fmi2StringToValueReference?

[sathvikbhagavan]

I saw the code for fmi2ValueReferenceToString and fmi2StringToValueReference. The functions fmi2GetNamesToValueReference and fmi2GetValueRefenceToName are similar but gives out a dictionary for all modelVariables.