Design of optimal Runge-Kutta methods - FEniCS Project
Design of optimal Runge-Kutta methods - FEniCS Project
Design of optimal Runge-Kutta methods - FEniCS Project
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Accuracy optimization<br />
We could instead optimize accuracy over some region in C:<br />
Accuracy optimization<br />
Given L, p, s,<br />
maximize ∆t<br />
subject to |φ(∆tλ) − exp(∆tλ| ≤ ɛ, λ ∈ σ(L),<br />
where<br />
p� 1<br />
φ(z) =<br />
j! zj +<br />
s�<br />
αjz j .<br />
j=0<br />
j=p+1<br />
In the PDE case, we can replace exp(∆tλ) with the exact dispersion<br />
relation for each Fourier mode.<br />
D. Ketcheson (KAUST) 13 / 36