GMRES with non-standard inner product

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Hi,

today I tried to use your GMRES solver with a custom inner product, but this appears to be a poorly tested codepath. Namely, there is a typo in the constructor, self.restart is not set and after the restart the new inner product is not forwarded.

Namely, I had to make the following changes to make it work:

[code]diff --git a/home/alex/devel/src/ngsolve/python/krylovspace.py b/krylovspace.py
index ea97030…e9d88ce 100644
— a/home/alex/devel/src/ngsolve/python/krylovspace.py
+++ b/krylovspace.py
@@ -713,8 +713,9 @@ restart : int = None
**kwargs):
super().init(*args, **kwargs)
if innerproduct is not None:

  •        self.innnerproduct = innerproduct

  •        self.innerproduct = innerproduct
       self.norm = lambda x: sqrt(innerproduct(x,x).real)

  •        self.restart = restart
   else:
       self.innerproduct = lambda x, y: y.InnerProduct(x, conjugate=True)
       self.norm = Norm

@@ -820,6 +821,7 @@ restart : int = None
callback_sol=self.callback_sol,
maxiter=self.maxiter,
restart=self.restart,

  •                                           innerproduct=self.innerproduct,
                                          printrates=self.printrates)
           restarted_solver.iterations = self.iterations
           sol = restarted_solver.Solve(rhs = rhs, sol = sol, initialize=False)

[/code]

best,
Alex