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view stencilEquation.m @ 1217:a3d9567d9004 feature/d2_compatible

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Improve efficiency of construction of D2(b) by precomputing as much as possible
author Martin Almquist <malmquist@stanford.edu>
date Wed, 13 Nov 2019 14:54:22 -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