view stencilEquation.m @ 1065:c2bd7f15da48 feature/laplace_curvilinear_test

Add scheme where only corner points are multiplied by dim. Does not seem to decrease spectral radius much, but is stable.
author Martin Almquist <malmquist@stanford.edu>
date Thu, 17 Jan 2019 18:57:54 -0800
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