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annotate stencilEquation.m @ 1016:4b42999874c0 feature/advectionRV

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Add lower level for boot-strapping to RungeKuttaExteriorRV - Add a lower level to RungeKuttaExteriorRV for which bootstrapping starts, e.g start bootstrapping from time level 3 using a 3rd order BDF - Clean up ResidualViscosity
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 07 Dec 2018 13:11:53 +0100
parents 184833fe4c0e
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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660
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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1 % Find the equation for the stencil for d^k/dx^k
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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2 function [A,b] = stencilEquation(k, offsets, order)
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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3 q = sym('q', [1, length(offsets)]);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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5 p = 0:(order-1+k);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
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184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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7 v = vandermonde(offsets, p);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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8 vdiff = vandermonde( 0, p-k);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
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184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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10 eq = q*v == vdiff;
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
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184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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12 [A,b] = equationsToMatrix(eq, q);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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