Mercurial > repos > public > sbplib
comparison +sbp/+implementations/d4_variable_6_min_boundary_points.m @ 316:203afa156f59 feature/beams
Collected boundary operators.
author | Jonatan Werpers <jonatan@werpers.com> |
---|---|
date | Fri, 23 Sep 2016 23:10:44 +0200 |
parents | 9230c056a574 |
children | 99005a80b4c2 |
comparison
equal
deleted
inserted
replaced
315:297d2cbfbe15 | 316:203afa156f59 |
---|---|
20 | 20 |
21 H = diag(ones(m,1),0); | 21 H = diag(ones(m,1),0); |
22 H(1:6,1:6) = diag([13649/43200,12013/8640,2711/4320,5359/4320,7877/8640, 43801/43200]); | 22 H(1:6,1:6) = diag([13649/43200,12013/8640,2711/4320,5359/4320,7877/8640, 43801/43200]); |
23 H(m-5:m,m-5:m) = fliplr(flipud(diag([13649/43200,12013/8640, 2711/4320,5359/4320,7877/8640,43801/43200]))); | 23 H(m-5:m,m-5:m) = fliplr(flipud(diag([13649/43200,12013/8640, 2711/4320,5359/4320,7877/8640,43801/43200]))); |
24 | 24 |
25 e_1 = zeros(m,1);e_1(1)=1; | |
26 e_m = zeros(m,1);e_m(m)=1; | |
27 | |
28 S_U = [-25/12, 4, -3, 4/3, -1/4]/h; | |
29 S_1 = zeros(1,m); | |
30 S_1(1:5) = S_U; | |
31 S_m = zeros(1,m); | |
32 S_m(m-4:m) = fliplr(-S_U); | |
33 | |
34 S2_U = [0.35e2/0.12e2 -0.26e2/0.3e1 0.19e2/0.2e1 -0.14e2/0.3e1 0.11e2/0.12e2;]/h^2; | |
35 S2_1 = zeros(1,m); | |
36 S2_1(1:5) = S2_U; | |
37 S2_m = zeros(1,m); | |
38 S2_m(m-4:m) = fliplr(S2_U); | |
39 | |
40 S3_U = [-0.5e1/0.2e1 9 -12 7 -0.3e1/0.2e1;]/h^3; | |
41 S3_1 = zeros(1,m); | |
42 S3_1(1:5) = S3_U; | |
43 S3_m = zeros(1,m); | |
44 S3_m(m-4:m) = fliplr(-S3_U); | |
45 | |
25 | 46 |
26 x1=0.70127127127127; | 47 x1=0.70127127127127; |
27 | 48 |
28 | 49 |
29 D1=(1/60*diag(ones(m-3,1),3)-9/60*diag(ones(m-2,1),2)+45/60*diag(ones(m-1,1),1)-45/60*diag(ones(m-1,1),-1)+9/60*diag(ones(m-2,1),-2)-1/60*diag(ones(m-3,1),-3)); | 50 D1=(1/60*diag(ones(m-3,1),3)-9/60*diag(ones(m-2,1),2)+45/60*diag(ones(m-1,1),1)-45/60*diag(ones(m-1,1),-1)+9/60*diag(ones(m-2,1),-2)-1/60*diag(ones(m-3,1),-3)); |
36 34560/7877*x1-147127/47262, -129600/7877*x1+91715/7877, 172800/7877*x1-242111/15754, -86400/7877*x1+165041/23631, 0, 8640/7877*x1, -1296/7877, 144/7877, 0; | 57 34560/7877*x1-147127/47262, -129600/7877*x1+91715/7877, 172800/7877*x1-242111/15754, -86400/7877*x1+165041/23631, 0, 8640/7877*x1, -1296/7877, 144/7877, 0; |
37 -43200/43801*x1+89387/131403, 172800/43801*x1-240569/87602, -259200/43801*x1+182261/43801, 172800/43801*x1-710473/262806, -43200/43801*x1, 0, 32400/43801, -6480/43801, 720/43801 | 58 -43200/43801*x1+89387/131403, 172800/43801*x1-240569/87602, -259200/43801*x1+182261/43801, 172800/43801*x1-710473/262806, -43200/43801*x1, 0, 32400/43801, -6480/43801, 720/43801 |
38 ]; | 59 ]; |
39 D1(m-5:m,m-8:m) = flipud( fliplr(-D1(1:6,1:9))); | 60 D1(m-5:m,m-8:m) = flipud( fliplr(-D1(1:6,1:9))); |
40 D1 = D1/h; | 61 D1 = D1/h; |
41 | |
42 e_1 = zeros(m,1);e_1(1)=1; | |
43 e_m = zeros(m,1);e_m(m)=1; | |
44 | |
45 S_U = [-25/12, 4, -3, 4/3, -1/4]/h; | |
46 S_1 = zeros(1,m); | |
47 S_1(1:5) = S_U; | |
48 S_m = zeros(1,m); | |
49 S_m(m-4:m) = fliplr(-S_U); | |
50 | |
51 | |
52 %DS=zeros(m,m); | |
53 %DS(1,1:5)=-[-25/12, 4, -3, 4/3, -1/4]; | |
54 %DS(m,m-4:m)=fliplr(-[-25/12, 4, -3, 4/3, -1/4]); | |
55 %DS=diag(c)*DS/h; | |
56 | 62 |
57 | 63 |
58 H = h*H; | 64 H = h*H; |
59 HI = inv(H); | 65 HI = inv(H); |
60 | 66 |
95 | 101 |
96 M = M/h; | 102 M = M/h; |
97 | 103 |
98 D2 = HI*(-M-diag(c)*e_1*S_1+diag(c)*e_m*S_m); | 104 D2 = HI*(-M-diag(c)*e_1*S_1+diag(c)*e_m*S_m); |
99 | 105 |
100 S2_U = [0.35e2/0.12e2 -0.26e2/0.3e1 0.19e2/0.2e1 -0.14e2/0.3e1 0.11e2/0.12e2;]/h^2; | |
101 S2_1 = zeros(1,m); | |
102 S2_1(1:5) = S2_U; | |
103 S2_m = zeros(1,m); | |
104 S2_m(m-4:m) = fliplr(S2_U); | |
105 | |
106 | |
107 | |
108 | |
109 | 106 |
110 % Fourth derivative, 1th order accurate at first 8 boundary points (still | 107 % Fourth derivative, 1th order accurate at first 8 boundary points (still |
111 % yield 5th order convergence if stable: for example u_tt=-u_xxxx | 108 % yield 5th order convergence if stable: for example u_tt=-u_xxxx |
112 | 109 |
113 m4 = 7/240; | 110 m4 = 7/240; |
132 M4(1:6,1:6) = M4_U; | 129 M4(1:6,1:6) = M4_U; |
133 | 130 |
134 M4(m-5:m,m-5:m) = flipud( fliplr( M4_U ) ); | 131 M4(m-5:m,m-5:m) = flipud( fliplr( M4_U ) ); |
135 M4 = M4/h^3; | 132 M4 = M4/h^3; |
136 | 133 |
137 S3_U = [-0.5e1/0.2e1 9 -12 7 -0.3e1/0.2e1;]/h^3; | |
138 S3_1 = zeros(1,m); | |
139 S3_1(1:5) = S3_U; | |
140 S3_m = zeros(1,m); | |
141 S3_m(m-4:m) = fliplr(-S3_U); | |
142 | |
143 D4 = HI*(M4-e_1*S3_1+e_m*S3_m + S_1'*S2_1-S_m'*S2_m); | 134 D4 = HI*(M4-e_1*S3_1+e_m*S3_m + S_1'*S2_1-S_m'*S2_m); |
144 | 135 |
145 end | 136 end |