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view stencilEquation.m @ 1015:9b7fcd5e4480 feature/advectionRV

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Debug ResidualViscosity - Pass exact time derivative to RungeKuttaExteriorRV and use that for evaluating the residual - Start bootstrapping from later time level with higher order bdf
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Thu, 06 Dec 2018 17:03:22 +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