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Conflicting start values

Conflicting start values

I've been going round and round in circles trying to resolve this type of warning:

Code:


[1] 12:05:14 Symbolic Warning
The model contains alias variables with conflicting start and/or nominal values. It is recommended to resolve the conflicts, because otherwise the system could be hard to solve. To print the conflicting alias sets and the chosen candidates please use -d=aliasConflicts.

I've simplified the problem down to the simplest example I can in the attached scratch2.mo file. It's very simple, a revolute joint with two bodyCylinders connected to it like a pendulum. The angle condition in the revolute joint specifies the starting angle of the pendulum, I want the two cylinders connected to it to initialise according to this. The problem is that whether I set the initialisation conditions of the bodyCylinders to "false" or "inherited" (I can see no difference in behaviour between these two cases) I always get this warning when I have the two cylinders connected up like this. (If I set them to true then not-surprisingly it refuses to solve as expected). Just one cylinder is fine, it's the second one that causes the warning message to appear.

For this simple case it still solves and does what I want. But the model I'm working on is way more complicated than this and I'm getting very problematic behaviour or just not solving at all which I think is caused by various elements trying to impose initial conditions that I don't want. Why won't it take 'false' for an answer?!  current/mad

I'm using MSL 3.2.3 and OMEdit with 1.15.0~dev-49.
scratch2.mo

Edited by: trilbytim - Jun-10-20 13:02:12
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