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Discuss the concept of superconvergence better. #10703

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merged 1 commit into from Sep 16, 2020
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bangerth
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Following up on a discussion on the mailing list with @cpraveen .

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@tjhei tjhei left a comment

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Interesting! I made a few suggestions that made the description flow a bit better. Feel free to pick and choose.

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All good points -- thanks, guys! Fixed.

// at. It turns out that the result we get depends quite sensitively on the
// "quadrature" points being used. There is also the issue of
// superconvergence: Finite element solutions are, on some meshes and for
// polynomial degrees $k\ge 2$, particularly accurate at the node points as
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Its not worth changing, but you still get order 2k convergence for linear elements: its just that k + 1 = 2 * k in that case :)

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We are technically superconvergent at the Gauss-Lobatto points, not just the Gauss points (i.e., we get order 2*k convergence at mesh nodes too). Otherwise 👍

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Sorry, I meant to mark the other review as 'request changes'.

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drwells commented Sep 3, 2020

@bangerth ping

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@drwells comment addressed.

@masterleinad masterleinad merged commit a4c9a88 into dealii:master Sep 16, 2020
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5 participants