Use Kokkos::Parallel in Solver Utils

[julianlitz]

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[julianlitz]

@EmilyBourne Can you make "ExactSolution" callable on GPU? Then all Kokkos Loops should be finished.

[EmilyBourne]

@EmilyBourne Can you make "ExactSolution" callable on GPU? Then all Kokkos Loops should be finished.

Ah, I had hoped to avoid this 😅 I will open a PR to remove the inheritance from ExactSolution so it can be called from GPU

[EmilyBourne]

@EmilyBourne Can you make "ExactSolution" callable on GPU? Then all Kokkos Loops should be finished.

Ah, I had hoped to avoid this 😅 I will open a PR to remove the inheritance from ExactSolution so it can be called from GPU

I have put this in draft temporarily until this is fixed

[EmilyBourne]

@EmilyBourne Can you make "ExactSolution" callable on GPU? Then all Kokkos Loops should be finished.

Ah, I had hoped to avoid this 😅 I will open a PR to remove the inheritance from ExactSolution so it can be called from GPU

I have put this in draft temporarily until this is fixed

Actually we can avoid removing the inheritance. We just need to put either a

void calculate_error(Vector<double> error, ConstVector<T> r, ConstVector<T> theta, ConstVector<T> exact_solution) const;

method in ExactSolver or a method:

void exact_solution(ConstVector<T> r, ConstVector<T> theta, Vector<T> exact) const;

@AbdelhadiKara will take care of this