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view stencilEquation.m @ 1039:a8ee5eca0e6c feature/burgers1d

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Allow for the residual normalization function to return a vector. Also change the default normalization from normalizing on norm(u-mean(u),inf) to norm(u/2), since this proved to be better for 1d burgers
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 18 Jan 2019 09:06:20 +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