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comparison +sbp/+implementations/d2_2.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
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260:b4116ce49ac4 261:6009f2712d13
1 function [H, HI, D1, D2, e_1, e_m, M, Q, S_1, S_m] = d2_2(m,h)
2 e_1=zeros(m,1);e_1(1)=1;
3 e_m=zeros(m,1);e_m(m)=1;
4
5 H=(eye(m,m));H(1,1)=0.5;H(m,m)=0.5;
6 H=h*H;
7 HI=inv(H);
8
9 D1=((.5*diag(ones(m-1,1),1)-.5*diag(ones(m-1,1),-1)));
10 D1(1,1)=-1;D1(1,2)=1;D1(m,m-1)=-1;D1(m,m)=1;
11 D1(m,m-1)=-1;D1(m,m)=1;
12 D1=D1/h;
13
14 Q=H*D1 + 1/2*e_1*e_1' - 1/2*e_m*e_m';
15
16 D2=((diag(ones(m-1,1),1)+diag(ones(m-1,1),-1)-2*diag(ones(m,1),0)));
17 D2(1,1)=1;D2(1,2)=-2;D2(1,3)=1;
18 D2(m,m-2)=1;D2(m,m-1)=-2;D2(m,m)=1;
19 D2=D2/h^2;
20
21 S_U=[-3/2, 2, -1/2]/h;
22 S_1=zeros(1,m);
23 S_1(1:3)=S_U;
24 S_m=zeros(1,m);
25 S_m(m-2:m)=fliplr(-S_U);
26
27
28 M=-H*D2-e_1*S_1+e_m*S_m;
29 S_1 = S_1';
30 S_m = S_m';
31 end