**First EPM test**
🏠 [Home]("https://blog.linearconstraints.net") ✉ ounanding@gmail.com 📅 Mon Jan 18 21:47:11 PST 2021
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Now I have my initial setup ready to solve a coupled system $P=F(X),X=S(P)$
with partitioned method. It would be interesting to compare it with the
Gauss-Seidel style solver in the previous post. Unfortunately at the moment I
do not have a monolithic solver so it is difficult to tell which one is better.

Gauss-Seidel solver and EPM have very close appearance using the previous
setup. So this time I have to use a different one, where multiple rigid bodies
can interact through fluid.
    
The EPM result with 2 iterations looks close to the Gauss-Seidel one with 8
iterations. I also plot the angle of the top right rigid box between 400-500
frames in different simulations. Most of the results feel convincing to me.
However I cannot explain why they do not converge monotonically to a value as
more iterations are used.
