annotate +sbp/+implementations/d2_variable_hollow_2.m @ 1337:bf2554f1825d feature/D2_boundary_opt

Add periodic D1 and D2 operators for orders 8,10,12
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 13 May 2022 13:28:10 +0200
parents b5907140c069
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
1303
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
1 function [H, HI, D1, D2, e_l, e_r, d1_l, d1_r] = d2_variable_hollow_2(m,h)
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
2
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
3 BP = 1;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
4 if(m<2*BP)
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
5 error(['Operator requires at least ' num2str(2*BP) ' grid points']);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
6 end
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
7
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
8 % Norm
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
9 Hv = ones(m,1);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
10 Hv(1) = 1/2;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
11 Hv(m:m) = 1/2;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
12 Hv = h*Hv;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
13 H = spdiag(Hv, 0);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
14 HI = spdiag(1./Hv, 0);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
15
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
16
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
17 % Boundary operators
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
18 e_l = sparse(m,1);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
19 e_l(1) = 1;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
20 e_r = rot90(e_l, 2);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
21
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
22 d1_l = sparse(m,1);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
23 d1_l(1:3) = 1/h*[-3/2 2 -1/2];
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
24 d1_r = -rot90(d1_l, 2);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
25
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
26 % D1 operator
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
27 diags = -1:1;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
28 stencil = [-1/2 0 1/2];
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
29 D1 = stripeMatrix(stencil, diags, m);
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
30
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
31 D1(1,1)=-1;D1(1,2)=1;D1(m,m-1)=-1;D1(m,m)=1;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
32 D1(m,m-1)=-1;D1(m,m)=1;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
33 D1=D1/h;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
34 %Q=H*D1 + 1/2*(e_1*e_1') - 1/2*(e_m*e_m');
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
35
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
36
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
37 nBP = 2;
1305
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
38 M = sparse(m,m);
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
39 coeffs = load('sbplib/+sbp/+implementations/coeffs_d2_variable_2.mat');
1303
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
40
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
41 function D2 = D2_fun(c)
1305
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
42 M_l = zeros(nBP, coeffs.nBPC);
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
43 M_r = zeros(nBP, coeffs.nBPC);
1303
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
44
1305
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
45 for i=1:coeffs.nBPC
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
46 M_l = M_l + coeffs.C_l{i}*c(i);
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
47 M_r = M_r + coeffs.C_r{i}*c(m-coeffs.nBPC+i);
1303
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
48 end
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
49
1305
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
50 M(1:nBP, 1:coeffs.nBPC) = M_l;
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
51 M(m-nBP+1:m, m-coeffs.nBPC+1:m) = M_r;
1303
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
52
1305
b5907140c069 Clean up hollow D2 generation by using precomputed coefficients stored in mat files
Martin Almquist <malmquist@stanford.edu>
parents: 1303
diff changeset
53 D2 = M/h^2;
1303
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
54 end
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
55 D2 = @D2_fun;
49e3870335ef Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
Martin Almquist <malmquist@stanford.edu>
parents:
diff changeset
56 end