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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

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