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comparison +sbp/+implementations/d2_4.m @ 307:fefb2f9884f7 feature/beams

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Merge with default.
author Jonatan Werpers <jonatan@werpers.com>
date Fri, 23 Sep 2016 10:40:12 +0200
parents f7ac3cd6eeaa
children 8b8672134be8
comparison
equal deleted inserted replaced
306:8368beb0d1b3 307:fefb2f9884f7
1 function [H, HI, D1, D2, e_1, e_m, M, Q, S_1, S_m] = d2_4(m,h)
2
3 BP = 4;
4 if(m<2*BP)
5 error(['Operator requires at least ' num2str(2*BP) ' grid points']);
6 end
7
8 e_1=sparse(m,1);e_1(1)=1;
9 e_m=sparse(m,1);e_m(m)=1;
10
11 e=ones(m,1);
12 H=spdiags(e,0,m,m);
13 %H=speye(m,m);
14
15 H(1:4,1:4)=diag([17/48 59/48 43/48 49/48]);
16 H(m-3:m,m-3:m)=rot90(diag([17/48 59/48 43/48 49/48]),2);
17 H=H*h;
18 HI=inv(H);
19
20
21 Q=spdiags([e -8*e 0*e 8*e -e], -2:2, m, m)/12;
22 %Q=(-1/12*diag(ones(m-2,1),2)+8/12*diag(ones(m-1,1),1)-8/12*diag(ones(m-1,1),-1)+1/12*diag(ones(m-2,1),-2));
23 Q_U = [0 0.59e2 / 0.96e2 -0.1e1 / 0.12e2 -0.1e1 / 0.32e2; -0.59e2 / 0.96e2 0 0.59e2 / 0.96e2 0; 0.1e1 / 0.12e2 -0.59e2 / 0.96e2 0 0.59e2 / 0.96e2; 0.1e1 / 0.32e2 0 -0.59e2 / 0.96e2 0;];
24 Q(1:4,1:4)=Q_U;
25 Q(m-3:m,m-3:m)=rot90( -Q_U(1:4,1:4) ,2 );
26
27 D1=H\(Q-1/2*(e_1*e_1')+1/2*(e_m*e_m')) ;
28
29 M=-spdiags([-e 16*e -30*e 16*e -e], -2:2, m, m)/12;
30
31 %M=-(-1/12*diag(ones(m-2,1),2)+16/12*diag(ones(m-1,1),1)+16/12*diag(ones(m-1,1),-1)-1/12*diag(ones(m-2,1),-2)-30/12*diag(ones(m,1),0));
32
33 M_U=[0.9e1 / 0.8e1 -0.59e2 / 0.48e2 0.1e1 / 0.12e2 0.1e1 / 0.48e2; -0.59e2 / 0.48e2 0.59e2 / 0.24e2 -0.59e2 / 0.48e2 0; 0.1e1 / 0.12e2 -0.59e2 / 0.48e2 0.55e2 / 0.24e2 -0.59e2 / 0.48e2; 0.1e1 / 0.48e2 0 -0.59e2 / 0.48e2 0.59e2 / 0.24e2;];
34 M(1:4,1:4)=M_U;
35
36 M(m-3:m,m-3:m)=rot90( M_U ,2 );
37 M=M/h;
38
39 S_U=[-0.11e2 / 0.6e1 3 -0.3e1 / 0.2e1 0.1e1 / 0.3e1;]/h;
40 S_1=sparse(sparse(1,m));
41 S_1(1:4)=S_U;
42 S_m=sparse(sparse(1,m));
43 S_m(m-3:m)=fliplr(-S_U);
44
45
46 D2=H\(-M-e_1*S_1+e_m*S_m);
47 S_1 = S_1';
48 S_m = S_m';
49 end