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view stencilEquation.m @ 993:44e7e497c3b7 feature/timesteppers

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Make time.rk.General accept a butcher tableau instead of a string to choose method. String variant implemented as a static method
author Jonatan Werpers <jonatan@werpers.com>
date Wed, 09 Jan 2019 11:14:16 +0100
parents 184833fe4c0e
children
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% Find the equation for the stencil for d^k/dx^k
function [A,b] = stencilEquation(k, offsets, order)
    q = sym('q', [1, length(offsets)]);

    p = 0:(order-1+k);

    v     = vandermonde(offsets, p);
    vdiff = vandermonde(      0, p-k);

    eq = q*v == vdiff;

    [A,b] = equationsToMatrix(eq, q);
end