Mercurial > repos > public > sbplib

view stencilEquation.m @ 851:ab2e5a24ddde feature/burgers1d

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
- Fix bug when constructing closure for narrow stencils - Update the residual outside of the RK time steps. At least for the inner convergence rate, updating the residual inside does not seem to be required.
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 21 Sep 2018 15:33:15 +0200
parents 184833fe4c0e
children
line wrap: on
line source

% 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