Mercurial > repos > public > sbplib

annotate stencilEquation.m @ 975:47b48a97c675 feature/getBoundaryOperator

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Stupid merge makes this branch dangerous. Merging with other branches will result in unexpected changes. Never merge this branch with anything. Closing branch.
author Martin Almquist <malmquist@stanford.edu>
date Thu, 03 Jan 2019 13:24:39 +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:
diff changeset
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:
diff changeset
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:
diff changeset
6
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
7 v = vandermonde(offsets, p);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
8 vdiff = vandermonde( 0, p-k);
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
9
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
10 eq = q*v == vdiff;
184833fe4c0e Add monomial, vandermonde and stencil cretation tools
Jonatan Werpers <jonatan@werpers.com>
parents:
diff changeset
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