roccaa

Sorry for the delay. Here an example with the bug (do `siconos run.cpp` to compile it). One of the interaction is linked to two DS. [example.zip](https://github.com/siconos/siconos/files/7001578/example.zip) The system and its...

Currently I do not really know which matrix it is, I guess it is the W matrix in the compute free state, I will check it ? In the old...

Ok I found what happen. the matrix W becomes singular at some point. It happens here: ```c++ // At this point xfree = (ResiduFree - h(1-gamma)*rold) // -> Solve WX...

Ok, this is a bit misleading then when displaying the matrix ... :) But then, I really do not see why the solve fails.

Ok, I will pull and re-install siconos from scratch, maybe the `make uninstall` I usually run before an update did not do the trick correctly and there is some side-effect...

Ok I still have the same error even If I switched to the commit you specified. I guess it is my installation which is flawed (again) ? I did a...

@bremond I see. If I want to work with numpy as inputs (and as observers ... ), as first need to initialize this numpy object as recasted pointer to siconos...

Yes wrapping effect is the biggest problem. On this technique there is no magic solution to my best knowledge. We can always use the classical trick: splitting, adaptive time steps,...

I think it is a classic algorithm in robotic for collision detection. Maybe you can find some example of it in this domain.