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comparison +sbp/+implementations/d1_upwind_4.m @ 261:6009f2712d13 operator_remake

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Moved and renamned all implementations.
author Martin Almquist <martin.almquist@it.uu.se>
date Thu, 08 Sep 2016 15:35:45 +0200
parents
children bfa130b7abf6
comparison
equal deleted inserted replaced
260:b4116ce49ac4 261:6009f2712d13
1 function [H, HI, Dp, Dm, e_1, e_m] = d1_upwind_4(m,h)
2
3 Hv=ones(m,1);
4 Hv(1:4)=[49/144 61/48 41/48 149/144];
5 Hv(m-3:m)=rot90(Hv(1:4),2);
6 Hv = Hv*h;
7 H = spdiag(Hv,0);
8 HI = spdiag(1./Hv,0);
9
10 q_diags = [-1, 0, 1, 2 3];
11 q_stencil = [-1/4 -5/6 3/2 -1/2 1/12];
12 Qp = stripeMatrix(q_stencil, q_diags,m);
13
14 Q_U = [
15 -0.1e1/0.48e2 0.205e3/0.288e3 -0.29e2/0.144e3 0.1e1/0.96e2;
16 -0.169e3/0.288e3 -0.11e2/0.48e2 0.33e2/0.32e2 -0.43e2/0.144e3;
17 0.11e2/0.144e3 -0.13e2/0.32e2 -0.29e2/0.48e2 0.389e3/0.288e3;
18 0.1e1/0.32e2 -0.11e2/0.144e3 -0.65e2/0.288e3 -0.13e2/0.16e2;
19 ];
20
21 Qp(1:4,1:4)=Q_U;
22 Qp(m-3:m,m-3:m)=rot90(Q_U,2)'; %%% This is different from standard SBP
23
24 Qm=-Qp';
25
26 e_1=sparse(m,1);e_1(1)=1;
27 e_m=sparse(m,1);e_m(m)=1;
28
29 Dp=HI*(Qp-1/2*e_1*e_1'+1/2*e_m*e_m') ;
30
31 Dm=HI*(Qm-1/2*e_1*e_1'+1/2*e_m*e_m') ;
32 end