Differentiation of homotopy

[Adrian Pop]

See the attached model.

loadFile("cis.mo"); getErrorString();
simulate(ThermoPower.Examples.CISE.CISESim120501); getErrorString();

gives:

[c:\\bin\\cygwin\\home\\adrpo\\dev\\OpenModelicaNoChanges\\build\\bin\\b\\ThermoPower\\cis.mo:1631:7-1631:195:writable] Error: Internal error 
Differentiate.differentiateEquationTime failed for Plant.Downcomer.h[1] = homotopy(Plant.Drum.afd * Plant.Drum.hf + (1.0 - Plant.Drum.afd) * Plant.Drum.hl, Plant.Drum.afd * Plant.Drum.hf + (1.0 - Plant.Drum.afd) * Plant.Drum.hl)


Error: Internal error - IndexReduction.pantelidesIndexReduction1 failed! Use +d=bltdump to get more information.
Error: Internal error - IndexReduction.pantelidesIndexReduction failed!
Error: Internal error Transformation Module PFPlusExt index Reduction Method Pantelides failed!

[Adrian Pop]

I guess we need to do:

diff(homotopy(e1, e2)) -> homotopy(diff(e1), diff(e2))

The questions is what should we do after that.
Do we have any support for homotopy?

[Adrian Pop]

Fixed in r18671. Seems we do handle homotopy in initialization.
Added test also as now the model ThermoPower.Examples.CISE.CISESim120501 simulates.
No check of results yet.

[Adrian Pop]

Damn, this fix breaks Modelica.Fluid.Examples.HeatingSystem and 2 AVM models.
I will comment it out for now and maybe Willi can come up with a better fix.

[Adrian Pop]

Hm, the problem was that we had homotopy(e, e).
I now commented out:

diff(homotopy(e1, e2)) -> homotopy(diff(e1), diff(e2))

and added simplification:

homotopy(e, e) -> e

which hopefully is OK.
I'll keep this ticked open even if the given model works.

[Martin Sjölund]

This ticket was not closed for 1.9.1, which has now been released. It was batch modified for milestone 1.9.2 (but maybe an empty milestone was more appropriate; feel free to change it).

[Francesco Casella]

The original test case now works successfully. As there was no further feedback in the last 12 months, I guess we can close the ticket.