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annotate stencilEquation.m @ 1330:855871e0b852 feature/D2_boundary_opt

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Add size checks to the operators
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Thu, 17 Feb 2022 18:55:11 +0100
parents 184833fe4c0e
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
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:
diff changeset
2 function [A,b] = stencilEquation(k, offsets, order)
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
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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4
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
5 p = 0:(order-1+k);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
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6
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>
parents:
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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>
parents:
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11
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
12 [A,b] = equationsToMatrix(eq, q);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
13 end