changeset 1303:49e3870335ef feature/poroelastic

Make the hollow scheme generation more efficient by introducing the D2VariableHollow opSet
author Martin Almquist <malmquist@stanford.edu>
date Sat, 11 Jul 2020 06:54:15 -0700
parents a0d615bde7f8
children a38e80fdbf60
files +sbp/+implementations/d2_variable_hollow_2.m +sbp/+implementations/d2_variable_hollow_4.m +sbp/+implementations/d4_variable_hollow_6.m +sbp/D2VariableCompatibleHollow.m +scheme/Elastic2dVariableAnisotropic.m
diffstat 5 files changed, 467 insertions(+), 6 deletions(-) [+]
line wrap: on
line diff
diff -r a0d615bde7f8 -r 49e3870335ef +sbp/+implementations/d2_variable_hollow_2.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/+sbp/+implementations/d2_variable_hollow_2.m	Sat Jul 11 06:54:15 2020 -0700
@@ -0,0 +1,72 @@
+function [H, HI, D1, D2, e_l, e_r, d1_l, d1_r] = d2_variable_hollow_2(m,h)
+
+    BP = 1;
+    if(m<2*BP)
+        error(['Operator requires at least ' num2str(2*BP) ' grid points']);
+    end
+
+    % Norm
+    Hv = ones(m,1);
+    Hv(1) = 1/2;
+    Hv(m:m) = 1/2;
+    Hv = h*Hv;
+    H = spdiag(Hv, 0);
+    HI = spdiag(1./Hv, 0);
+
+
+    % Boundary operators
+    e_l = sparse(m,1);
+    e_l(1) = 1;
+    e_r = rot90(e_l, 2);
+
+    d1_l = sparse(m,1);
+    d1_l(1:3) = 1/h*[-3/2 2 -1/2];
+    d1_r = -rot90(d1_l, 2);
+
+    % D1 operator
+    diags   = -1:1;
+    stencil = [-1/2 0 1/2];
+    D1 = stripeMatrix(stencil, diags, m);
+
+    D1(1,1)=-1;D1(1,2)=1;D1(m,m-1)=-1;D1(m,m)=1;
+    D1(m,m-1)=-1;D1(m,m)=1;
+    D1=D1/h;
+    %Q=H*D1 + 1/2*(e_1*e_1') - 1/2*(e_m*e_m');
+
+
+    M=sparse(m,m);
+    nBP = 2;
+
+    scheme_width = 3;
+    scheme_radius = (scheme_width-1)/2;
+
+    function D2 = D2_fun(c)
+
+        for r = 1+scheme_radius:nBP
+            Mm1 = -c(r-1)/2 - c(r)/2;
+            M0  =  c(r-1)/2 + c(r)   + c(r+1)/2;
+            Mp1 =            -c(r)/2 - c(r+1)/2;
+
+            M(r, r-1) = Mm1;
+            M(r, r) = M0;
+            M(r, r+1) = Mp1;
+        end
+
+        for r = m-nBP+1:m-scheme_radius
+            Mm1 = -c(r-1)/2 - c(r)/2;
+            M0  =  c(r-1)/2 + c(r)   + c(r+1)/2;
+            Mp1 =            -c(r)/2 - c(r+1)/2;
+
+            M(r, r-1) = Mm1;
+            M(r, r) = M0;
+            M(r, r+1) = Mp1;
+        end
+
+        M(1:2,1:2)=[c(1)/2 + c(2)/2 -c(1)/2 - c(2)/2; -c(1)/2 - c(2)/2 c(1)/2 + c(2) + c(3)/2;];
+        M(m-1:m,m-1:m)=[c(m-2)/2 + c(m-1) + c(m)/2 -c(m-1)/2 - c(m)/2; -c(m-1)/2 - c(m)/2 c(m-1)/2 + c(m)/2;];
+        M=M/h;
+
+        D2=HI*(-M-c(1)*e_l*d1_l'+c(m)*e_r*d1_r');
+    end
+    D2 = @D2_fun;
+end
\ No newline at end of file
diff -r a0d615bde7f8 -r 49e3870335ef +sbp/+implementations/d2_variable_hollow_4.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/+sbp/+implementations/d2_variable_hollow_4.m	Sat Jul 11 06:54:15 2020 -0700
@@ -0,0 +1,136 @@
+function [H, HI, D1, D2, e_l, e_r, d1_l, d1_r] = d2_variable_hollow_4(m,h)
+
+    BP = 6;
+    if(m<2*BP)
+        error(['Operator requires at least ' num2str(2*BP) ' grid points']);
+    end
+
+
+
+
+    % Norm
+    Hv = ones(m,1);
+    Hv(1:4) = [17/48 59/48 43/48 49/48];
+    Hv(m-3:m) = rot90(Hv(1:4),2);
+    Hv = h*Hv;
+    H = spdiag(Hv, 0);
+    HI = spdiag(1./Hv, 0);
+
+
+    % Boundary operators
+    e_l = sparse(m,1);
+    e_l(1) = 1;
+    e_r = rot90(e_l, 2);
+
+    d1_l = sparse(m,1);
+    d1_l(1:4) = 1/h*[-11/6 3 -3/2 1/3];
+    d1_r = -rot90(d1_l, 2);
+
+
+
+
+    S = d1_l*d1_l' + d1_r*d1_r';
+
+    stencil = [1/12 -2/3 0 2/3 -1/12];
+    diags = -2:2;
+
+    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;
+    ];
+
+    Q = stripeMatrix(stencil, diags, m);
+    Q(1:4,1:4) = Q_U;
+    Q(m-3:m,m-3:m) = -rot90(Q_U, 2);
+
+    D1 = HI*(Q - 1/2*e_l*e_l' + 1/2*e_r*e_r');
+
+
+    N = m;
+    function D2 = D2_fun(c)
+        M = 78+(N-12)*5;
+        %h = 1/(N-1);
+
+
+        U = [
+            48/(17)*(0.12e2/0.17e2 * c(1) + 0.59e2/0.192e3 * c(2) + 0.27010400129e11/0.345067064608e12 * c(3) + 0.69462376031e11/0.2070402387648e13 * c(4)) 48/(17)*(-0.59e2/0.68e2 * c(1) - 0.6025413881e10/0.21126554976e11 * c(3) - 0.537416663e9/0.7042184992e10 * c(4)) 48/(17)*(0.2e1/0.17e2 * c(1) - 0.59e2/0.192e3 * c(2) + 0.213318005e9/0.16049630912e11 * c(4) + 0.2083938599e10/0.8024815456e10 * c(3)) 48/(17)*(0.3e1/0.68e2 * c(1) - 0.1244724001e10/0.21126554976e11 * c(3) + 0.752806667e9/0.21126554976e11 * c(4)) 48/(17)*(0.49579087e8/0.10149031312e11 * c(3) - 0.49579087e8/0.10149031312e11 * c(4)) 48/(17)*(-c(4)/0.784e3 + c(3)/0.784e3);...
+            48/(59)*(-0.59e2/0.68e2 * c(1) - 0.6025413881e10/0.21126554976e11 * c(3) - 0.537416663e9/0.7042184992e10 * c(4)) 48/(59)*(0.3481e4/0.3264e4 * c(1) + 0.9258282831623875e16/0.7669235228057664e16 * c(3) + 0.236024329996203e15/0.1278205871342944e16 * c(4)) 48/(59)*(-0.59e2/0.408e3 * c(1) - 0.29294615794607e14/0.29725717938208e14 * c(3) - 0.2944673881023e13/0.29725717938208e14 * c(4)) 48/(59)*(-0.59e2/0.1088e4 * c(1) + 0.260297319232891e15/0.2556411742685888e16 * c(3) - 0.60834186813841e14/0.1278205871342944e16 * c(4)) 48/(59)*(-0.1328188692663e13/0.37594290333616e14 * c(3) + 0.1328188692663e13/0.37594290333616e14 * c(4)) 48/(59)*(-0.8673e4/0.2904112e7 * c(3) + 0.8673e4/0.2904112e7 * c(4));...
+            48/(43)*(0.2e1/0.17e2 * c(1) - 0.59e2/0.192e3 * c(2) + 0.213318005e9/0.16049630912e11 * c(4) + 0.2083938599e10/0.8024815456e10 * c(3)) 48/(43)*(-0.59e2/0.408e3 * c(1) - 0.29294615794607e14/0.29725717938208e14 * c(3) - 0.2944673881023e13/0.29725717938208e14 * c(4)) 48/(43)*(c(1)/0.51e2 + 0.59e2/0.192e3 * c(2) + 0.13777050223300597e17/0.26218083221499456e17 * c(4) + 0.564461e6/0.13384296e8 * c(5) + 0.378288882302546512209e21/0.270764341349677687456e21 * c(3)) 48/(43)*(c(1)/0.136e3 - 0.125059e6/0.743572e6 * c(5) - 0.4836340090442187227e19/0.5525802884687299744e19 * c(3) - 0.17220493277981e14/0.89177153814624e14 * c(4)) 48/(43)*(-0.10532412077335e14/0.42840005263888e14 * c(4) + 0.1613976761032884305e19/0.7963657098519931984e19 * c(3) + 0.564461e6/0.4461432e7 * c(5)) 48/(43)*(-0.960119e6/0.1280713392e10 * c(4) - 0.3391e4/0.6692148e7 * c(5) + 0.33235054191e11/0.26452850508784e14 * c(3));...
+            48/(49)*(0.3e1/0.68e2 * c(1) - 0.1244724001e10/0.21126554976e11 * c(3) + 0.752806667e9/0.21126554976e11 * c(4)) 48/(49)*(-0.59e2/0.1088e4 * c(1) + 0.260297319232891e15/0.2556411742685888e16 * c(3) - 0.60834186813841e14/0.1278205871342944e16 * c(4)) 48/(49)*(c(1)/0.136e3 - 0.125059e6/0.743572e6 * c(5) - 0.4836340090442187227e19/0.5525802884687299744e19 * c(3) - 0.17220493277981e14/0.89177153814624e14 * c(4)) 48/(49)*(0.3e1/0.1088e4 * c(1) + 0.507284006600757858213e21/0.475219048083107777984e21 * c(3) + 0.1869103e7/0.2230716e7 * c(5) + c(6)/0.24e2 + 0.1950062198436997e16/0.3834617614028832e16 * c(4)) 48/(49)*(-0.4959271814984644613e19/0.20965546238960637264e20 * c(3) - c(6)/0.6e1 - 0.15998714909649e14/0.37594290333616e14 * c(4) - 0.375177e6/0.743572e6 * c(5)) 48/(49)*(-0.368395e6/0.2230716e7 * c(5) + 0.752806667e9/0.539854092016e12 * c(3) + 0.1063649e7/0.8712336e7 * c(4) + c(6)/0.8e1);...
+            0.49579087e8/0.10149031312e11 * c(3) - 0.49579087e8/0.10149031312e11 * c(4) -0.1328188692663e13/0.37594290333616e14 * c(3) + 0.1328188692663e13/0.37594290333616e14 * c(4) -0.10532412077335e14/0.42840005263888e14 * c(4) + 0.1613976761032884305e19/0.7963657098519931984e19 * c(3) + 0.564461e6/0.4461432e7 * c(5) -0.4959271814984644613e19/0.20965546238960637264e20 * c(3) - c(6)/0.6e1 - 0.15998714909649e14/0.37594290333616e14 * c(4) - 0.375177e6/0.743572e6 * c(5) 0.8386761355510099813e19/0.128413970713633903242e21 * c(3) + 0.2224717261773437e16/0.2763180339520776e16 * c(4) + 0.5e1/0.6e1 * c(6) + c(7)/0.24e2 + 0.280535e6/0.371786e6 * c(5) -0.35039615e8/0.213452232e9 * c(4) - c(7)/0.6e1 - 0.13091810925e11/0.13226425254392e14 * c(3) - 0.1118749e7/0.2230716e7 * c(5) - c(6)/0.2e1;...
+            -c(4)/0.784e3 + c(3)/0.784e3 -0.8673e4/0.2904112e7 * c(3) + 0.8673e4/0.2904112e7 * c(4) -0.960119e6/0.1280713392e10 * c(4) - 0.3391e4/0.6692148e7 * c(5) + 0.33235054191e11/0.26452850508784e14 * c(3) -0.368395e6/0.2230716e7 * c(5) + 0.752806667e9/0.539854092016e12 * c(3) + 0.1063649e7/0.8712336e7 * c(4) + c(6)/0.8e1 -0.35039615e8/0.213452232e9 * c(4) - c(7)/0.6e1 - 0.13091810925e11/0.13226425254392e14 * c(3) - 0.1118749e7/0.2230716e7 * c(5) - c(6)/0.2e1 0.3290636e7/0.80044587e8 * c(4) + 0.5580181e7/0.6692148e7 * c(5) + 0.5e1/0.6e1 * c(7) + c(8)/0.24e2 + 0.660204843e9/0.13226425254392e14 * c(3) + 0.3e1/0.4e1 * c(6)
+        ];
+
+
+        L = [
+            c(N-7)/0.24e2 + 0.5e1/0.6e1 * c(N-6) + 0.5580181e7/0.6692148e7 * c(N-4) + 0.4887707739997e13/0.119037827289528e15 * c(N-3) + 0.3e1/0.4e1 * c(N-5) + 0.660204843e9/0.13226425254392e14 * c(N-2) + 0.660204843e9/0.13226425254392e14 * c(N-1) -c(N-6)/0.6e1 - 0.1618585929605e13/0.9919818940794e13 * c(N-3) - c(N-5)/0.2e1 - 0.1118749e7/0.2230716e7 * c(N-4) - 0.13091810925e11/0.13226425254392e14 * c(N-2) - 0.13091810925e11/0.13226425254392e14 * c(N-1) -0.368395e6/0.2230716e7 * c(N-4) + c(N-5)/0.8e1 + 0.48866620889e11/0.404890569012e12 * c(N-3) + 0.752806667e9/0.539854092016e12 * c(N-2) + 0.752806667e9/0.539854092016e12 * c(N-1) -0.3391e4/0.6692148e7 * c(N-4) - 0.238797444493e12/0.119037827289528e15 * c(N-3) + 0.33235054191e11/0.26452850508784e14 * c(N-2) + 0.33235054191e11/0.26452850508784e14 * c(N-1) -0.8673e4/0.2904112e7 * c(N-2) - 0.8673e4/0.2904112e7 * c(N-1) + 0.8673e4/0.1452056e7 * c(N-3) -c(N-3)/0.392e3 + c(N-2)/0.784e3 + c(N-1)/0.784e3;...
+           -c(N-6)/0.6e1 - 0.1618585929605e13/0.9919818940794e13 * c(N-3) - c(N-5)/0.2e1 - 0.1118749e7/0.2230716e7 * c(N-4) - 0.13091810925e11/0.13226425254392e14 * c(N-2) - 0.13091810925e11/0.13226425254392e14 * c(N-1) c(N-6)/0.24e2 + 0.5e1/0.6e1 * c(N-5) + 0.3896014498639e13/0.4959909470397e13 * c(N-3) + 0.8386761355510099813e19/0.128413970713633903242e21 * c(N-2) + 0.280535e6/0.371786e6 * c(N-4) + 0.3360696339136261875e19/0.171218627618178537656e21 * c(N-1) -c(N-5)/0.6e1 - 0.4959271814984644613e19/0.20965546238960637264e20 * c(N-2) - 0.375177e6/0.743572e6 * c(N-4) - 0.13425842714e11/0.33740880751e11 * c(N-3) - 0.193247108773400725e18/0.6988515412986879088e19 * c(N-1) -0.365281640980e12/0.1653303156799e13 * c(N-3) + 0.564461e6/0.4461432e7 * c(N-4) + 0.1613976761032884305e19/0.7963657098519931984e19 * c(N-2) - 0.198407225513315475e18/0.7963657098519931984e19 * c(N-1) -0.1328188692663e13/0.37594290333616e14 * c(N-2) + 0.2226377963775e13/0.37594290333616e14 * c(N-1) - 0.8673e4/0.363014e6 * c(N-3) c(N-3)/0.49e2 + 0.49579087e8/0.10149031312e11 * c(N-2) - 0.256702175e9/0.10149031312e11 * c(N-1);...
+           48/(49)*(-0.368395e6/0.2230716e7 * c(N-4) + c(N-5)/0.8e1 + 0.48866620889e11/0.404890569012e12 * c(N-3) + 0.752806667e9/0.539854092016e12 * c(N-2) + 0.752806667e9/0.539854092016e12 * c(N-1)) 48/(49)*(-c(N-5)/0.6e1 - 0.4959271814984644613e19/0.20965546238960637264e20 * c(N-2) - 0.375177e6/0.743572e6 * c(N-4) - 0.13425842714e11/0.33740880751e11 * c(N-3) - 0.193247108773400725e18/0.6988515412986879088e19 * c(N-1)) 48/(49)*(c(N-5)/0.24e2 + 0.1869103e7/0.2230716e7 * c(N-4) + 0.507284006600757858213e21/0.475219048083107777984e21 * c(N-2) + 0.3e1/0.1088e4 * c(N) + 0.31688435395e11/0.67481761502e11 * c(N-3) + 0.27769176016102795561e20/0.712828572124661666976e21 * c(N-1)) 48/(49)*(-0.125059e6/0.743572e6 * c(N-4) + c(N)/0.136e3 - 0.23099342648e11/0.101222642253e12 * c(N-3) - 0.4836340090442187227e19/0.5525802884687299744e19 * c(N-2) + 0.193950157930938693e18/0.5525802884687299744e19 * c(N-1)) 48/(49)*(0.260297319232891e15/0.2556411742685888e16 * c(N-2) - 0.59e2/0.1088e4 * c(N) - 0.106641839640553e15/0.1278205871342944e16 * c(N-1) + 0.26019e5/0.726028e6 * c(N-3)) 48/(49)*(-0.1244724001e10/0.21126554976e11 * c(N-2) + 0.3e1/0.68e2 * c(N) + 0.752806667e9/0.21126554976e11 * c(N-1));...
+           48/(43)*(-0.3391e4/0.6692148e7 * c(N-4) - 0.238797444493e12/0.119037827289528e15 * c(N-3) + 0.33235054191e11/0.26452850508784e14 * c(N-2) + 0.33235054191e11/0.26452850508784e14 * c(N-1)) 48/(43)*(-0.365281640980e12/0.1653303156799e13 * c(N-3) + 0.564461e6/0.4461432e7 * c(N-4) + 0.1613976761032884305e19/0.7963657098519931984e19 * c(N-2) - 0.198407225513315475e18/0.7963657098519931984e19 * c(N-1)) 48/(43)*(-0.125059e6/0.743572e6 * c(N-4) + c(N)/0.136e3 - 0.23099342648e11/0.101222642253e12 * c(N-3) - 0.4836340090442187227e19/0.5525802884687299744e19 * c(N-2) + 0.193950157930938693e18/0.5525802884687299744e19 * c(N-1)) 48/(43)*(0.564461e6/0.13384296e8 * c(N-4) + 0.470299699916357e15/0.952302618316224e15 * c(N-3) + 0.550597048646198778781e21/0.1624586048098066124736e22 * c(N-1) + c(N)/0.51e2 + 0.378288882302546512209e21/0.270764341349677687456e21 * c(N-2)) 48/(43)*(-0.59e2/0.408e3 * c(N) - 0.29294615794607e14/0.29725717938208e14 * c(N-2) - 0.2234477713167e13/0.29725717938208e14 * c(N-1) - 0.8673e4/0.363014e6 * c(N-3)) 48/(43)*(-0.59e2/0.3136e4 * c(N-3) - 0.13249937023e11/0.48148892736e11 * c(N-1) + 0.2e1/0.17e2 * c(N) + 0.2083938599e10/0.8024815456e10 * c(N-2));...
+           48/(59)*(-0.8673e4/0.2904112e7 * c(N-2) - 0.8673e4/0.2904112e7 * c(N-1) + 0.8673e4/0.1452056e7 * c(N-3)) 48/(59)*(-0.1328188692663e13/0.37594290333616e14 * c(N-2) + 0.2226377963775e13/0.37594290333616e14 * c(N-1) - 0.8673e4/0.363014e6 * c(N-3)) 48/(59)*(0.260297319232891e15/0.2556411742685888e16 * c(N-2) - 0.59e2/0.1088e4 * c(N) - 0.106641839640553e15/0.1278205871342944e16 * c(N-1) + 0.26019e5/0.726028e6 * c(N-3)) 48/(59)*(-0.59e2/0.408e3 * c(N) - 0.29294615794607e14/0.29725717938208e14 * c(N-2) - 0.2234477713167e13/0.29725717938208e14 * c(N-1) - 0.8673e4/0.363014e6 * c(N-3)) 48/(59)*(0.9258282831623875e16/0.7669235228057664e16 * c(N-2) + 0.3481e4/0.3264e4 * c(N) + 0.228389721191751e15/0.1278205871342944e16 * c(N-1) + 0.8673e4/0.1452056e7 * c(N-3)) 48/(59)*(-0.6025413881e10/0.21126554976e11 * c(N-2) - 0.59e2/0.68e2 * c(N) - 0.537416663e9/0.7042184992e10 * c(N-1));...
+           48/(17)*(-c(N-3)/0.392e3 + c(N-2)/0.784e3 + c(N-1)/0.784e3) 48/(17)*(c(N-3)/0.49e2 + 0.49579087e8/0.10149031312e11 * c(N-2) - 0.256702175e9/0.10149031312e11 * c(N-1)) 48/(17)*(-0.1244724001e10/0.21126554976e11 * c(N-2) + 0.3e1/0.68e2 * c(N) + 0.752806667e9/0.21126554976e11 * c(N-1)) 48/(17)*(-0.59e2/0.3136e4 * c(N-3) - 0.13249937023e11/0.48148892736e11 * c(N-1) + 0.2e1/0.17e2 * c(N) + 0.2083938599e10/0.8024815456e10 * c(N-2)) 48/(17)*(-0.6025413881e10/0.21126554976e11 * c(N-2) - 0.59e2/0.68e2 * c(N) - 0.537416663e9/0.7042184992e10 * c(N-1)) 48/(17)*(0.3e1/0.3136e4 * c(N-3) + 0.27010400129e11/0.345067064608e12 * c(N-2) + 0.234566387291e12/0.690134129216e12 * c(N-1) + 0.12e2/0.17e2 * c(N))
+        ];
+
+
+        M = 78;
+        R = sparse(M,1);
+        R(1:24) = reshape(U(1:4,:)',24,1);
+        R(25:30) = U(5,:);
+        R(31) = -c(5+1)/0.6e1 + c(5)/0.8e1 + c(5+2)/0.8e1;
+        R(32:37) = U(6,:);
+        R(38:39) = [-c(6-1)/0.6e1 - c(6+2)/0.6e1 - c(6)/0.2e1 - c(6+1)/0.2e1;...
+                                      -c(6+1)/0.6e1 + c(6)/0.8e1 + c(6+2)/0.8e1];
+
+        R(M-38:M-37) = [-c(N-6)/0.6e1 + c(N-7)/0.8e1 + c(N-5)/0.8e1;...
+                                              -c(N-7)/0.6e1 - c(N-4)/0.6e1 - c(N-6)/0.2e1 - c(N-5)/0.2e1];
+        R(M-36:M-31) = L(1,:);
+        R(M-30) = -c(N-5)/0.6e1 + c(N-6)/0.8e1 + c(N-4)/0.8e1;
+        R(M-29:M-24) = L(2,:);
+        R(M-23:M) = reshape(L(3:6,:)',24,1);
+
+        % for i=7:N-6
+        %     R(40+(i-7)*5:44+(i-7)*5) = [
+        %         -c(i-1)/0.6e1 + c(i-2)/0.8e1 + c(i)/0.8e1,...
+        %         -c(i-2)/0.6e1 - c(i+1)/0.6e1 - c(i-1)/0.2e1 - c(i)/0.2e1,...
+        %         c(i-2)/0.24e2 + 0.5e1/0.6e1 * c(i-1) + 0.5e1/0.6e1 * c(i+1) + c(i+2)/0.24e2 + 0.3e1/0.4e1 * c(i),...
+        %         -c(i-1)/0.6e1 - c(i+2)/0.6e1 - c(i)/0.2e1 - c(i+1)/0.2e1,...
+        %         -c(i+1)/0.6e1 + c(i)/0.8e1 + c(i+2)/0.8e1
+        %     ];
+        % end
+
+        R = R/h/h;
+        D2 = -R;
+        D2(1:4) = -48/17/h/h*[c(1)*(-11/6);c(1)*3;c(1)*(-3/2);c(1)*1/3] + D2(1:4);
+        D2(M-3:M) = -48/17/h/h*[c(N)*1/3;c(N)*(-3/2);c(N)*3;c(N)*(-11/6)] + D2(M-3:M);
+
+
+
+%         BS = sparse(N,N);
+%         BS(1,1:4) = -c(1)*1/h*[(-11/6);3;(-3/2);1/3];
+%         BS(N,N-3:N) = c(N)*1/h*[(-1/3);3/2;(-3);11/6];
+%         BS = sparse(BS);
+
+    % %%Row and column indices%%
+        rows = [kron([1;2;3;4],ones(6,1));...
+                    5*ones(7,1);...
+                    6*ones(8,1);...
+                    % kron((7:N-6)',ones(5,1));...
+                    (N-5)*ones(8,1);...
+                    (N-4)*ones(7,1);...
+                    kron([N-3;N-2;N-1;N],ones(6,1))];
+
+        cols = sparse(M,1);
+        cols(1:24) = kron(ones(4,1),[1;2;3;4;5;6]);
+        cols(25:39) = [(1:7)';(1:8)'];
+        cols(M-23:M) = kron(ones(4,1),[N-5;N-4;N-3;N-2;N-1;N]);
+        cols(M-38:M-24) = [(N-7:N)';(N-6:N)'];
+        % for i=7:N-6
+        %     cols(40+(i-7)*5:44+(i-7)*5) = (i-2:i+2)';
+        % end
+        D2 = sparse(rows,cols,D2);
+
+    end
+    D2 = @D2_fun;
+end
\ No newline at end of file
diff -r a0d615bde7f8 -r 49e3870335ef +sbp/+implementations/d4_variable_hollow_6.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/+sbp/+implementations/d4_variable_hollow_6.m	Sat Jul 11 06:54:15 2020 -0700
@@ -0,0 +1,164 @@
+function [H, HI, D1, D2, D4, e_l, e_r, M4, d2_l, d2_r, d3_l, d3_r, d1_l, d1_r] = d4_variable_hollow_6(m,h)
+    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+    %%% 6:te ordn. SBP Finita differens         %%%
+    %%% operatorer med diagonal norm            %%%
+    %%% Extension to variable koeff             %%%
+    %%%                                         %%%
+    %%% H           (Normen)                    %%%
+    %%% D1=H^(-1)Q  (approx f?rsta derivatan)   %%%
+    %%% D2          (approx andra derivatan)    %%%
+    %%% D2=HI*(R+C*D*S                          %%%
+    %%%                                         %%%
+    %%% R=-D1'*H*C*D1-RR                        %%%
+    %%%                                         %%%
+    %%% RR ?r dissipation)                      %%%
+    %%% Dissipationen uppbyggd av D4:           %%%
+    %%% DI=D4*B*H*D4                            %%%
+    %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+    BP = 9;
+    if(m<2*BP)
+        error(['Operator requires at least ' num2str(2*BP) ' grid points']);
+    end
+
+    % Norm
+    Hv = ones(m,1);
+    Hv(1:6) = [13649/43200,12013/8640,2711/4320,5359/4320,7877/8640, 43801/43200];
+    Hv(m-5:m) = rot90(Hv(1:6),2);
+    Hv = h*Hv;
+    H = spdiag(Hv, 0);
+    HI = spdiag(1./Hv, 0);
+
+
+    % Boundary operators
+    e_l = sparse(m,1);
+    e_l(1) = 1;
+    e_r = rot90(e_l, 2);
+
+    d1_l = sparse(m,1);
+    d1_l(1:5) = [-25/12, 4, -3, 4/3, -1/4]/h;
+    d1_r = -rot90(d1_l, 2);
+
+    d2_l = sparse(m,1);
+    d2_l(1:5) = [0.35e2/0.12e2 -0.26e2/0.3e1 0.19e2/0.2e1 -0.14e2/0.3e1 0.11e2/0.12e2;]/h^2;
+    d2_r = rot90(d2_l, 2);
+
+    d3_l = sparse(m,1);
+    d3_l(1:5) = [-5/2 9 -12 7 -3/2]/h^3;
+    d3_r = -rot90(d3_l, 2);
+
+
+    % First derivtive
+    x1=0.70127127127127;
+
+
+    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));
+
+
+
+    D1(1:6,1:9)=[-21600/13649, 43200/13649*x1-7624/40947, -172800/13649*x1+ ...
+    	     715489/81894, 259200/13649*x1-187917/13649, -172800/13649* ...
+    	     x1+735635/81894, 43200/13649*x1-89387/40947, 0, 0, 0; ...
+    	     -8640/12013*x1+7624/180195, 0, 86400/12013*x1-57139/12013, ...
+    	     -172800/12013*x1+745733/72078, 129600/12013*x1-91715/12013, ...
+    	     -34560/12013*x1+240569/120130, 0, 0, 0; ...
+             17280/2711*x1-715489/162660, -43200/2711*x1+57139/5422, 0, ...
+             86400/2711*x1-176839/8133, -86400/2711*x1+242111/10844, ...
+             25920/2711*x1-182261/27110, 0, 0, 0; ...
+             -25920/5359*x1+187917/53590, 86400/5359*x1-745733/64308, ...
+             -86400/5359*x1+176839/16077, 0, 43200/5359*x1-165041/32154, ...
+             -17280/5359*x1+710473/321540, 72/5359, 0, 0; ...
+             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; ...
+             -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];
+    D1(m-5:m,m-8:m)=rot90( -D1(1:6,1:9),2);
+    D1=D1/h;
+
+
+    % Second derivative
+    M=sparse(m,m);
+
+    nBP = 9;
+    scheme_width = 7;
+    scheme_radius = (scheme_width-1)/2;
+
+    function D2 = D2_fun(c)
+
+        for r = [(1+scheme_radius):nBP, m-nBP+1:m-scheme_radius]
+            Mm3 =  c(r-2)/0.40e2 + c(r-1)/0.40e2 - 0.11e2/0.360e3 * c(r-3) - 0.11e2/0.360e3 * c(r);
+            Mm2 =  c(r-3)/0.20e2 - 0.3e1/0.10e2 * c(r-1) + c(r+1)/0.20e2 + 0.7e1/0.40e2 * c(r) + 0.7e1/0.40e2 * c(r-2);
+            Mm1 = -c(r-3)/0.40e2 - 0.3e1/0.10e2 * c(r-2) - 0.3e1/0.10e2 * c(r+1) - c(r+2)/0.40e2 - 0.17e2/0.40e2 * c(r) - 0.17e2/0.40e2 * c(r-1);
+            M0 =  c(r-3)/0.180e3 + c(r-2)/0.8e1 + 0.19e2/0.20e2 * c(r-1) + 0.19e2/0.20e2 * c(r+1) + c(r+2)/0.8e1 + c(r+3)/0.180e3 + 0.101e3/0.180e3 * c(r);
+            Mp1 = -c(r-2)/0.40e2 - 0.3e1/0.10e2 * c(r-1) - 0.3e1/0.10e2 * c(r+2) - c(r+3)/0.40e2 - 0.17e2/0.40e2 * c(r) - 0.17e2/0.40e2 * c(r+1);
+            Mp2 =  c(r-1)/0.20e2 - 0.3e1/0.10e2 * c(r+1) + c(r+3)/0.20e2 + 0.7e1/0.40e2 * c(r) + 0.7e1/0.40e2 * c(r+2);
+            Mp3 =  c(r+1)/0.40e2 + c(r+2)/0.40e2 - 0.11e2/0.360e3 * c(r) - 0.11e2/0.360e3 * c(r+3);
+
+            M(r,r-3) = Mm3;
+            M(r,r-2) = Mm2;
+            M(r,r-1) = Mm1;
+            M(r,r) = M0;
+            M(r,r+1) = Mp1;
+            M(r,r+2) = Mp2;
+            M(r,r+3) = Mp3;
+        end
+
+        M(1:9,1:9)=[
+            0.7912667594695582093926295e0 * c(1) + 0.2968472090638000742888467e0 * c(2) + 0.3185519088796429015220016e-2 * c(3) + 0.1632404042590951953384672e-1 * c(4) + 0.3160302244094415087693968e-1 * c(5) + 0.3167964748016105299646518e-1 * c(6) + 0.3148577733947253920469418e-1 * c(7) -0.1016689339350338144430605e1 * c(1) - 0.2845627370491611369031341e-1 * c(3) - 0.4128029838349298819825156e-1 * c(4) - 0.1392281451620140507549866e0 * c(5) - 0.1195777325611201766551392e0 * c(6) - 0.1194267756529333410855186e0 * c(7) 0.7075642937243715046279337e-1 * c(1) - 0.1845476106024151050283847e0 * c(2) - 0.4364163147111892346990101e-1 * c(4) + 0.2432367907207732460874765e0 * c(5) + 0.1582127073537215443965653e0 * c(6) + 0.1602348578364786307613271e0 * c(7) 0.2251991532891353212689574e0 * c(1) - 0.1662748711097054895317080e0 * c(2) + 0.2710530961648671297733465e-1 * c(3) - 0.1916646185968439909125616e0 * c(5) - 0.7684117160199014594442072e-1 * c(6) - 0.8219586949831697575883635e-1 * c(7) -0.5224403464202056316702078e-1 * c(1) + 0.4440063948509876221050939e-1 * c(2) - 0.1023976547309387874453988e-2 * c(3) + 0.7403484645316174090533193e-1 * c(4) + 0.1241625568998496895352046e-1 * c(6) + 0.7188652847892601282652228e-1 * c(5) + 0.1379362997104735503447960e-1 * c(7) -0.1828896813877197352675410e-1 * c(1) + 0.9574633163221758060736592e-2 * c(2) - 0.8105784530576404277872603e-3 * c(3) - 0.7348845587775519698437916e-2 * c(4) + 0.1063601949723906997026904e-1 * c(5) - 0.1315967038382618382356495e-1 * c(6) - 0.2117936478838753524581943e-1 * c(7) 0.1911888563316170927411831e-2 * c(4) - 0.4068130355529149936100229e-1 * c(5) + 0.1319674981073749167009902e-1 * c(6) + 0.2557266518123783676349144e-1 * c(7) 0.1559652871136785763960685e-1 * c(5) - 0.6486184157331537899459796e-2 * c(6) - 0.9110344554036319740147054e-2 * c(7) 0.5593983696629863059347067e-3 * c(6) - 0.1384822535100796372263822e-2 * c(5) + 0.8254241654378100663291154e-3 * c(7);
+            -0.1016689339350338144430605e1 * c(1) - 0.2845627370491611369031341e-1 * c(3) - 0.4128029838349298819825156e-1 * c(4) - 0.1392281451620140507549866e0 * c(5) - 0.1195777325611201766551392e0 * c(6) - 0.1194267756529333410855186e0 * c(7) 0.1306332157111667628555907e1 * c(1) + 0.2542001760457345743492403e0 * c(3) + 0.1043897828092562609502636e0 * c(4) + 0.6672328021032112950919876e0 * c(5) + 0.4681819359722749441073885e0 * c(6) + 0.4676415410195836920069412e0 * c(7) -0.9091410269992464604926176e-1 * c(1) + 0.1103611313171476425250639e0 * c(4) - 0.1290397544997518887000350e1 * c(5) - 0.6639605248735044787146222e0 * c(6) - 0.6615974464005206184151509e0 * c(7) -0.2893557395653431666593814e0 * c(1) - 0.2421320004064592721552708e0 * c(3) + 0.1187670255028031027693374e1 * c(5) + 0.3956598149904136332753521e0 * c(6) + 0.3860048921755800000681479e0 * c(7) 0.6712774475803763988977355e-1 * c(1) + 0.9147192682075630179962131e-2 * c(3) - 0.1872196143003808021730728e0 * c(4) - 0.1319358558853174530078498e0 * c(6) - 0.4871575736811911887376923e0 * c(5) - 0.1047516312275448138054418e0 * c(7) 0.2349927974590068869356781e-1 * c(1) + 0.7240905383565181316381731e-2 * c(3) + 0.1858378996391679448655070e-1 * c(4) - 0.9289616133938676174345208e-1 * c(5) + 0.1223513270418807666970488e0 * c(6) + 0.1113520320436295033894092e0 * c(7) -0.4834791406446907590553793e-2 * c(4) + 0.2310683832687820403062715e0 * c(5) - 0.1080774142196007991746827e0 * c(6) - 0.1181561776427343335410349e0 * c(7) -0.8368141434403455353724691e-1 * c(5) + 0.4093499466767054661591066e-1 * c(6) + 0.4274641967636400692133626e-1 * c(7) -0.3576545132696983143406173e-2 * c(6) + 0.7389399124121078682094445e-2 * c(5) - 0.3812853991424095538688273e-2 * c(7);
+            0.7075642937243715046279337e-1 * c(1) - 0.1845476106024151050283847e0 * c(2) - 0.4364163147111892346990101e-1 * c(4) + 0.2432367907207732460874765e0 * c(5) + 0.1582127073537215443965653e0 * c(6) + 0.1602348578364786307613271e0 * c(7) -0.9091410269992464604926176e-1 * c(1) + 0.1103611313171476425250639e0 * c(4) - 0.1290397544997518887000350e1 * c(5) - 0.6639605248735044787146222e0 * c(6) - 0.6615974464005206184151509e0 * c(7) 0.6327161147136873807796515e-2 * c(1) + 0.1147318200715868527529827e0 * c(2) + 0.1166740554279680007487795e0 * c(4) + 0.2766610808285444037240703e1 * c(5) + 0.1070920689960817104203947e1 * c(6) + 0.1013161391032973057171717e1 * c(7) 0.2013769413884797246646959e-1 * c(1) + 0.1033717994630886401730470e0 * c(2) - 0.2913221621151742724258117e1 * c(5) - 0.8755807343482262259774782e0 * c(6) - 0.6909957183488812426508351e0 * c(7) -0.4671751091575462868310238e-2 * c(1) - 0.2760353365637712827793337e-1 * c(2) - 0.1979290298620869974478871e0 * c(4) + 0.5402985338373433052255418e0 * c(6) + 0.1239177593031911077924537e1 * c(5) + 0.2628038050247358227280031e0 * c(7) -0.1635430866921887819487473e-2 * c(1) - 0.5952475275883259619711594e-2 * c(2) + 0.1964682777744275219350831e-1 * c(4) + 0.3236640012639046600590714e0 * c(5) - 0.4659516693228870973898560e0 * c(6) - 0.2217272720941736859420432e0 * c(7) -0.5111353189352474549563559e-2 * c(4) - 0.5355878163774754346032096e0 * c(5) + 0.3328335104489738933610597e0 * c(6) + 0.2078656591178540157917135e0 * c(7) 0.1824328174134289562208038e0 * c(5) - 0.1059816030196818445908057e0 * c(6) - 0.7645121439374711162999809e-1 * c(7) 0.9209089963443799485648361e-2 * c(6) - 0.1591502818872493167091475e-1 * c(5) + 0.6705938225281132185266388e-2 * c(7);
+            0.2251991532891353212689574e0 * c(1) - 0.1662748711097054895317080e0 * c(2) + 0.2710530961648671297733465e-1 * c(3) - 0.1916646185968439909125616e0 * c(5) - 0.7684117160199014594442072e-1 * c(6) - 0.8219586949831697575883635e-1 * c(7) -0.2893557395653431666593814e0 * c(1) - 0.2421320004064592721552708e0 * c(3) + 0.1187670255028031027693374e1 * c(5) + 0.3956598149904136332753521e0 * c(6) + 0.3860048921755800000681479e0 * c(7) 0.2013769413884797246646959e-1 * c(1) + 0.1033717994630886401730470e0 * c(2) - 0.2913221621151742724258117e1 * c(5) - 0.8755807343482262259774782e0 * c(6) - 0.6909957183488812426508351e0 * c(7) 0.6409299775987186986730499e-1 * c(1) + 0.9313657638804699948929701e-1 * c(2) + 0.2306367624634749229113646e0 * c(3) + 0.3689440308283716620260816e1 * c(5) + 0.1190550338687608873798462e1 * c(6) + 0.5912479546888856519443605e0 * c(7) -0.1486895819265604128572498e-1 * c(1) - 0.2487040599390160764166412e-1 * c(2) - 0.8712928907711754187084757e-2 * c(3) - 0.1263507837371824205693950e1 * c(6) - 0.3058317397843997326920898e0 * c(7) - 0.1470691926045802954795783e1 * c(5) -0.5205147429855955657625694e-2 * c(1) - 0.5363098747528542488971874e-2 * c(2) - 0.6897142765790609546343709e-2 * c(3) - 0.7857524521667450101721993e0 * c(5) + 0.2291148005423734600066709e0 * c(7) + 0.9977064356292750529201981e0 * c(6) 0.6697297488067662265210608e0 * c(5) - 0.5013247356072127938999311e0 * c(6) - 0.1795161243106645437322408e0 * c(7) -0.2022909060111751565150958e0 * c(5) + 0.1453421858063658498587377e0 * c(6) + 0.5694872020480930665635812e-1 * c(7) -0.1200429618441003833696998e-1 * c(6) - 0.4776915669385923841535432e-2 * c(7) + 0.1678121185379596217850541e-1 * c(5);
+            -0.5224403464202056316702078e-1 * c(1) + 0.4440063948509876221050939e-1 * c(2) - 0.1023976547309387874453988e-2 * c(3) + 0.7403484645316174090533193e-1 * c(4) + 0.1241625568998496895352046e-1 * c(6) + 0.7188652847892601282652228e-1 * c(5) + 0.1379362997104735503447960e-1 * c(7) 0.6712774475803763988977355e-1 * c(1) + 0.9147192682075630179962131e-2 * c(3) - 0.1872196143003808021730728e0 * c(4) - 0.1319358558853174530078498e0 * c(6) - 0.4871575736811911887376923e0 * c(5) - 0.1047516312275448138054418e0 * c(7) -0.4671751091575462868310238e-2 * c(1) - 0.2760353365637712827793337e-1 * c(2) - 0.1979290298620869974478871e0 * c(4) + 0.5402985338373433052255418e0 * c(6) + 0.1239177593031911077924537e1 * c(5) + 0.2628038050247358227280031e0 * c(7) -0.1486895819265604128572498e-1 * c(1) - 0.2487040599390160764166412e-1 * c(2) - 0.8712928907711754187084757e-2 * c(3) - 0.1263507837371824205693950e1 * c(6) - 0.3058317397843997326920898e0 * c(7) - 0.1470691926045802954795783e1 * c(5) 0.3449455095910233625229891e-2 * c(1) + 0.6641183499427826101618457e-2 * c(2) + 0.3291545083271862858501887e-3 * c(3) + 0.3357721707576477199985656e0 * c(4) + 0.2096413329579026439044119e1 * c(6) + 0.2317323204183126854954203e0 * c(7) + 0.6107825764368264576481962e-2 * c(8) + 0.7109125850683376695640722e0 * c(5) 0.1207544072304193806052558e-2 * c(1) + 0.1432116665752147607469646e-2 * c(2) + 0.2605582646183255957264249e-3 * c(3) - 0.3332941113251635390801278e-1 * c(4) - 0.2808241697385532683612407e0 * c(7) - 0.2720908083525083608370563e-1 * c(8) + 0.1045865435682921987447929e0 * c(5) - 0.1348436986667115543203552e1 * c(6) 0.8671038084174692625075159e-2 * c(4) + 0.1736073411355428563685818e0 * c(6) + 0.5331362125287625412555844e-1 * c(8) - 0.2424935262404526301801157e0 * c(5) + 0.1569015257678588270609004e0 * c(7) -0.8631683980217122275970376e-1 * c(6) + 0.2698842360470999243492629e-1 * c(7) + 0.8098194147715651085292754e-1 * c(5) - 0.3276463639080639163926118e-1 * c(8) 0.7462059484530855073291365e-2 * c(6) - 0.8121640361668678949573496e-3 * c(7) + 0.5522702088127090209264064e-3 * c(8) - 0.7202165657176696199260422e-2 * c(5);
+            -0.1828896813877197352675410e-1 * c(1) + 0.9574633163221758060736592e-2 * c(2) - 0.8105784530576404277872603e-3 * c(3) - 0.7348845587775519698437916e-2 * c(4) + 0.1063601949723906997026904e-1 * c(5) - 0.1315967038382618382356495e-1 * c(6) - 0.2117936478838753524581943e-1 * c(7) 0.2349927974590068869356781e-1 * c(1) + 0.7240905383565181316381731e-2 * c(3) + 0.1858378996391679448655070e-1 * c(4) - 0.9289616133938676174345208e-1 * c(5) + 0.1223513270418807666970488e0 * c(6) + 0.1113520320436295033894092e0 * c(7) -0.1635430866921887819487473e-2 * c(1) - 0.5952475275883259619711594e-2 * c(2) + 0.1964682777744275219350831e-1 * c(4) + 0.3236640012639046600590714e0 * c(5) - 0.4659516693228870973898560e0 * c(6) - 0.2217272720941736859420432e0 * c(7) -0.5205147429855955657625694e-2 * c(1) - 0.5363098747528542488971874e-2 * c(2) - 0.6897142765790609546343709e-2 * c(3) - 0.7857524521667450101721993e0 * c(5) + 0.2291148005423734600066709e0 * c(7) + 0.9977064356292750529201981e0 * c(6) 0.1207544072304193806052558e-2 * c(1) + 0.1432116665752147607469646e-2 * c(2) + 0.2605582646183255957264249e-3 * c(3) - 0.3332941113251635390801278e-1 * c(4) - 0.2808241697385532683612407e0 * c(7) - 0.2720908083525083608370563e-1 * c(8) + 0.1045865435682921987447929e0 * c(5) - 0.1348436986667115543203552e1 * c(6) 0.4227226173449345042468960e-3 * c(1) + 0.3088241944378964404772302e-3 * c(2) + 0.2062575706647430620228133e-3 * c(3) + 0.3308343404200968256656458e-2 * c(4) + 0.5828047016405001815804837e0 * c(5) + 0.8054174220366215473556835e0 * c(7) + 0.1338363233410033443348225e0 * c(8) + 0.5555555555555555555555556e-2 * c(9) + 0.1190362071861893051132274e1 * c(6) -0.8607044252686413302647675e-3 * c(4) - 0.1748074708673904989293256e0 * c(5) - 0.3132544850115050165022338e0 * c(8) - 0.2500000000000000000000000e-1 * c(9) - 0.3169166305310429271303167e0 * c(7) - 0.6691607091647929161078591e0 * c(6) 0.3354661791693352108660900e-1 * c(5) - 0.3343620022386971405018586e0 * c(7) + 0.5000000000000000000000000e-1 * c(9) + 0.2169790609807602750804271e0 * c(6) + 0.1838363233410033443348225e0 * c(8) 0.2912518476823004642951502e-1 * c(7) + 0.2279091916474916391629437e-1 * c(8) - 0.3068985997518740530511593e-1 * c(6) - 0.1781799513347360596249022e-2 * c(5) - 0.3055555555555555555555556e-1 * c(9);
+            0.1911888563316170927411831e-2 * c(4) - 0.4068130355529149936100229e-1 * c(5) + 0.1319674981073749167009902e-1 * c(6) + 0.2557266518123783676349144e-1 * c(7) -0.4834791406446907590553793e-2 * c(4) + 0.2310683832687820403062715e0 * c(5) - 0.1080774142196007991746827e0 * c(6) - 0.1181561776427343335410349e0 * c(7) -0.5111353189352474549563559e-2 * c(4) - 0.5355878163774754346032096e0 * c(5) + 0.3328335104489738933610597e0 * c(6) + 0.2078656591178540157917135e0 * c(7) 0.6697297488067662265210608e0 * c(5) - 0.5013247356072127938999311e0 * c(6) - 0.1795161243106645437322408e0 * c(7) 0.8671038084174692625075159e-2 * c(4) + 0.1736073411355428563685818e0 * c(6) + 0.5331362125287625412555844e-1 * c(8) - 0.2424935262404526301801157e0 * c(5) + 0.1569015257678588270609004e0 * c(7) -0.8607044252686413302647675e-3 * c(4) - 0.1748074708673904989293256e0 * c(5) - 0.3132544850115050165022338e0 * c(8) - 0.2500000000000000000000000e-1 * c(9) - 0.3169166305310429271303167e0 * c(7) - 0.6691607091647929161078591e0 * c(6) 0.2239223735771599178951297e-3 * c(4) + 0.1275437785430956673825710e0 * c(5) + 0.1011699483929608164601067e1 * c(6) + 0.9698817275172575247533506e0 * c(8) + 0.1250000000000000000000000e0 * c(9) + 0.5555555555555555555555556e-2 * c(10) + 0.4823177543031281500117826e0 * c(7) -0.3784113973033012949863031e-1 * c(5) - 0.2997556885134827361576001e0 * c(6) - 0.3000000000000000000000000e0 * c(9) - 0.2500000000000000000000000e-1 * c(10) - 0.3991486867446821178415359e0 * c(7) - 0.4382544850115050165022338e0 * c(8) 0.4698146218022683933926520e-1 * c(6) - 0.2966863787471237458744416e0 * c(8) + 0.5000000000000000000000000e-1 * c(10) + 0.1716355704146006481727960e0 * c(7) + 0.3069346152296258362380356e-2 * c(5) + 0.1750000000000000000000000e0 * c(9);
+            0.1559652871136785763960685e-1 * c(5) - 0.6486184157331537899459796e-2 * c(6) - 0.9110344554036319740147054e-2 * c(7) -0.8368141434403455353724691e-1 * c(5) + 0.4093499466767054661591066e-1 * c(6) + 0.4274641967636400692133626e-1 * c(7) 0.1824328174134289562208038e0 * c(5) - 0.1059816030196818445908057e0 * c(6) - 0.7645121439374711162999809e-1 * c(7) -0.2022909060111751565150958e0 * c(5) + 0.1453421858063658498587377e0 * c(6) + 0.5694872020480930665635812e-1 * c(7) -0.8631683980217122275970376e-1 * c(6) + 0.2698842360470999243492629e-1 * c(7) + 0.8098194147715651085292754e-1 * c(5) - 0.3276463639080639163926118e-1 * c(8) 0.3354661791693352108660900e-1 * c(5) - 0.3343620022386971405018586e0 * c(7) + 0.5000000000000000000000000e-1 * c(9) + 0.2169790609807602750804271e0 * c(6) + 0.1838363233410033443348225e0 * c(8) -0.3784113973033012949863031e-1 * c(5) - 0.2997556885134827361576001e0 * c(6) - 0.3000000000000000000000000e0 * c(9) - 0.2500000000000000000000000e-1 * c(10) - 0.3991486867446821178415359e0 * c(7) - 0.4382544850115050165022338e0 * c(8) 0.1230328942716804455358698e-1 * c(5) + 0.1183647529645898332481833e0 * c(6) + 0.9410511898227943334189628e0 * c(7) + 0.9500000000000000000000000e0 * c(9) + 0.1250000000000000000000000e0 * c(10) + 0.5555555555555555555555556e-2 * c(11) + 0.5699474344521144554459336e0 * c(8) -0.2308067892671916339568942e-1 * c(6) - 0.2986625053775149497180439e0 * c(7) - 0.3000000000000000000000000e0 * c(10) - 0.2500000000000000000000000e-1 * c(11) - 0.1047734860515050802561078e-2 * c(5) - 0.4272090808352508360837056e0 * c(8) - 0.4250000000000000000000000e0 * c(9);
+            0.5593983696629863059347067e-3 * c(6) - 0.1384822535100796372263822e-2 * c(5) + 0.8254241654378100663291154e-3 * c(7) -0.3576545132696983143406173e-2 * c(6) + 0.7389399124121078682094445e-2 * c(5) - 0.3812853991424095538688273e-2 * c(7) 0.9209089963443799485648361e-2 * c(6) - 0.1591502818872493167091475e-1 * c(5) + 0.6705938225281132185266388e-2 * c(7) -0.1200429618441003833696998e-1 * c(6) - 0.4776915669385923841535432e-2 * c(7) + 0.1678121185379596217850541e-1 * c(5) 0.7462059484530855073291365e-2 * c(6) - 0.8121640361668678949573496e-3 * c(7) + 0.5522702088127090209264064e-3 * c(8) - 0.7202165657176696199260422e-2 * c(5) 0.2912518476823004642951502e-1 * c(7) + 0.2279091916474916391629437e-1 * c(8) - 0.3068985997518740530511593e-1 * c(6) - 0.1781799513347360596249022e-2 * c(5) - 0.3055555555555555555555556e-1 * c(9) 0.4698146218022683933926520e-1 * c(6) - 0.2966863787471237458744416e0 * c(8) + 0.5000000000000000000000000e-1 * c(10) + 0.1716355704146006481727960e0 * c(7) + 0.3069346152296258362380356e-2 * c(5) + 0.1750000000000000000000000e0 * c(9) -0.2308067892671916339568942e-1 * c(6) - 0.2986625053775149497180439e0 * c(7) - 0.3000000000000000000000000e0 * c(10) - 0.2500000000000000000000000e-1 * c(11) - 0.1047734860515050802561078e-2 * c(5) - 0.4272090808352508360837056e0 * c(8) - 0.4250000000000000000000000e0 * c(9) 0.5139370221149109977041877e-2 * c(6) + 0.1247723215009422001393184e0 * c(7) + 0.9505522702088127090209264e0 * c(8) + 0.9500000000000000000000000e0 * c(10) + 0.1250000000000000000000000e0 * c(11) + 0.5555555555555555555555556e-2 * c(12) + 0.9159362465153641826887659e-4 * c(5) + 0.5611111111111111111111111e0 * c(9);
+        ];
+
+        M(m-8:m,m-8:m)=[
+            0.5555555555555555555555556e-2 * c(m-11) + 0.1250000000000000000000000e0 * c(m-10) + 0.9500000000000000000000000e0 * c(m-9) + 0.9505522702088127090209264e0 * c(m-7) + 0.1247205076844361998744053e0 * c(m-6) + 0.5139370221149109977041877e-2 * c(m-5) + 0.5611111111111111111111111e0 * c(m-8) + 0.1434074411575366831819799e-3 * c(m-4) -0.2500000000000000000000000e-1 * c(m-10) - 0.3000000000000000000000000e0 * c(m-9) - 0.2980649679116425253322056e0 * c(m-6) - 0.2308067892671916339568942e-1 * c(m-5) - 0.4250000000000000000000000e0 * c(m-8) - 0.4272090808352508360837056e0 * c(m-7) - 0.1645272326387475188399322e-2 * c(m-4) 0.5000000000000000000000000e-1 * c(m-9) - 0.2966863787471237458744416e0 * c(m-7) + 0.4698146218022683933926520e-1 * c(m-5) + 0.1750000000000000000000000e0 * c(m-8) + 0.1700291833903489463825077e0 * c(m-6) + 0.4675733176547960152668626e-2 * c(m-4) 0.2279091916474916391629437e-1 * c(m-7) + 0.3097763128598982561225538e-1 * c(m-6) - 0.3055555555555555555555556e-1 * c(m-8) - 0.3068985997518740530511593e-1 * c(m-5) - 0.3634246031107139778989373e-2 * c(m-4) 0.5522702088127090209264064e-3 * c(m-7) - 0.3265435411305071914756373e-2 * c(m-6) + 0.7462059484530855073291365e-2 * c(m-5) - 0.4748894282038492179461399e-2 * c(m-4) 0.6272075574042975468177820e-3 * c(m-6) - 0.1200429618441003833696998e-1 * c(m-5) + 0.1137708862700574079015220e-1 * c(m-4) 0.9209089963443799485648361e-2 * c(m-5) - 0.3129629392354775191148163e-3 * c(m-6) - 0.8896127024208321966533544e-2 * c(m-4) -0.3576545132696983143406173e-2 * c(m-5) + 0.4335019854436220306755673e-3 * c(m-6) + 0.3143043147253361112730605e-2 * c(m-4) 0.5593983696629863059347067e-3 * c(m-5) - 0.1446656414398166805849327e-3 * c(m-6) - 0.4147327282231696253497740e-3 * c(m-4);
+            -0.2500000000000000000000000e-1 * c(m-10) - 0.3000000000000000000000000e0 * c(m-9) - 0.2980649679116425253322056e0 * c(m-6) - 0.2308067892671916339568942e-1 * c(m-5) - 0.4250000000000000000000000e0 * c(m-8) - 0.4272090808352508360837056e0 * c(m-7) - 0.1645272326387475188399322e-2 * c(m-4) 0.5555555555555555555555556e-2 * c(m-10) + 0.1250000000000000000000000e0 * c(m-9) + 0.9500000000000000000000000e0 * c(m-8) + 0.9341601509609901526962449e0 * c(m-6) + 0.1183647529645898332481833e0 * c(m-5) + 0.1919432828897222527630486e-1 * c(m-4) + 0.5699474344521144554459336e0 * c(m-7) -0.2500000000000000000000000e-1 * c(m-9) - 0.3000000000000000000000000e0 * c(m-8) - 0.2997556885134827361576001e0 * c(m-5) - 0.5636663150858098975790317e-1 * c(m-4) - 0.4382544850115050165022338e0 * c(m-7) - 0.3806231949664312575822630e0 * c(m-6) 0.5000000000000000000000000e-1 * c(m-8) - 0.3557251496099816106154206e0 * c(m-6) + 0.5490976528821799120017102e-1 * c(m-4) + 0.1838363233410033443348225e0 * c(m-7) + 0.2169790609807602750804271e0 * c(m-5) 0.5528052133944605740009217e-1 * c(m-6) - 0.8631683980217122275970376e-1 * c(m-5) - 0.3276463639080639163926118e-1 * c(m-7) + 0.5268984374242044588776166e-1 * c(m-4) -0.5373770512016897565958305e-2 * c(m-6) + 0.1453421858063658498587377e0 * c(m-5) - 0.1399684152943489522927794e0 * c(m-4) -0.1059816030196818445908057e0 * c(m-5) + 0.1014880675788250237247178e0 * c(m-4) + 0.4493535440856820866087846e-2 * c(m-6) 0.4093499466767054661591066e-1 * c(m-5) - 0.3471075437892810033585296e-1 * c(m-4) - 0.6224240288742446280057699e-2 * c(m-6) -0.6486184157331537899459796e-2 * c(m-5) + 0.4409068609809831485979484e-2 * c(m-4) + 0.2077115547521706413480312e-2 * c(m-6);
+            0.5000000000000000000000000e-1 * c(m-9) - 0.2966863787471237458744416e0 * c(m-7) + 0.4698146218022683933926520e-1 * c(m-5) + 0.1750000000000000000000000e0 * c(m-8) + 0.1700291833903489463825077e0 * c(m-6) + 0.4675733176547960152668626e-2 * c(m-4) -0.2500000000000000000000000e-1 * c(m-9) - 0.3000000000000000000000000e0 * c(m-8) - 0.2997556885134827361576001e0 * c(m-5) - 0.5636663150858098975790317e-1 * c(m-4) - 0.4382544850115050165022338e0 * c(m-7) - 0.3806231949664312575822630e0 * c(m-6) 0.5555555555555555555555556e-2 * c(m-9) + 0.1250000000000000000000000e0 * c(m-8) + 0.9698817275172575247533506e0 * c(m-7) + 0.1011699483929608164601067e1 * c(m-5) + 0.1773466968705924819112984e0 * c(m-4) + 0.2239223735771599178951297e-3 * c(m-3) + 0.4325148359756313354830552e0 * c(m-6) -0.2500000000000000000000000e-1 * c(m-8) - 0.3132544850115050165022338e0 * c(m-7) - 0.2322389872063761557916742e0 * c(m-4) - 0.8607044252686413302647675e-3 * c(m-3) - 0.2594851141920572702679681e0 * c(m-6) - 0.6691607091647929161078591e0 * c(m-5) 0.5331362125287625412555844e-1 * c(m-7) + 0.1736073411355428563685818e0 * c(m-5) + 0.8671038084174692625075159e-2 * c(m-3) + 0.8084259844422177692569663e-1 * c(m-6) - 0.1664345989168155800449120e0 * c(m-4) -0.5013247356072127938999311e0 * c(m-5) + 0.5021853752328231128475915e0 * c(m-4) - 0.1197175073672143005877150e-1 * c(m-6) 0.3328335104489738933610597e0 * c(m-5) - 0.3179803804558436283847901e0 * c(m-4) - 0.5111353189352474549563559e-2 * c(m-3) - 0.9741776803777790426705996e-2 * c(m-6) -0.1080774142196007991746827e0 * c(m-5) + 0.9941834083648937298100811e-1 * c(m-4) - 0.4834791406446907590553793e-2 * c(m-3) + 0.1349386478955833378422842e-1 * c(m-6) 0.1319674981073749167009902e-1 * c(m-5) - 0.1060554802883657391328704e-1 * c(m-4) + 0.1911888563316170927411831e-2 * c(m-3) - 0.4503090345217088684223814e-2 * c(m-6);
+            0.2279091916474916391629437e-1 * c(m-7) + 0.3097763128598982561225538e-1 * c(m-6) - 0.3055555555555555555555556e-1 * c(m-8) - 0.3068985997518740530511593e-1 * c(m-5) - 0.3634246031107139778989373e-2 * c(m-4) 0.5000000000000000000000000e-1 * c(m-8) - 0.3557251496099816106154206e0 * c(m-6) + 0.5490976528821799120017102e-1 * c(m-4) + 0.1838363233410033443348225e0 * c(m-7) + 0.2169790609807602750804271e0 * c(m-5) -0.2500000000000000000000000e-1 * c(m-8) - 0.3132544850115050165022338e0 * c(m-7) - 0.2322389872063761557916742e0 * c(m-4) - 0.8607044252686413302647675e-3 * c(m-3) - 0.2594851141920572702679681e0 * c(m-6) - 0.6691607091647929161078591e0 * c(m-5) 0.5555555555555555555555556e-2 * c(m-8) + 0.1338363233410033443348225e0 * c(m-7) + 0.7391887916719206077121040e0 * c(m-6) + 0.6490333320052011212240632e0 * c(m-4) + 0.3308343404200968256656458e-2 * c(m-3) + 0.2062575706647430620228133e-3 * c(m-2) + 0.3088241944378964404772302e-3 * c(m-1) + 0.4227226173449345042468960e-3 * c(m) + 0.1190362071861893051132274e1 * c(m-5) -0.2720908083525083608370563e-1 * c(m-7) - 0.1931148612480615118957263e0 * c(m-6) - 0.3332941113251635390801278e-1 * c(m-3) + 0.2605582646183255957264249e-3 * c(m-2) + 0.1432116665752147607469646e-2 * c(m-1) + 0.1207544072304193806052558e-2 * c(m) - 0.1348436986667115543203552e1 * c(m-5) + 0.1687723507780044227927853e-1 * c(m-4) 0.3590669644811151307464697e-1 * c(m-6) - 0.5925443480724830632401754e0 * c(m-4) - 0.6897142765790609546343709e-2 * c(m-2) - 0.5363098747528542488971874e-2 * c(m-1) - 0.5205147429855955657625694e-2 * c(m) + 0.9977064356292750529201981e0 * c(m-5) 0.7272438906214475928744770e-1 * c(m-4) + 0.1964682777744275219350831e-1 * c(m-3) - 0.5952475275883259619711594e-2 * c(m-1) - 0.1635430866921887819487473e-2 * c(m) + 0.2921234010758621482958052e-1 * c(m-6) - 0.4659516693228870973898560e0 * c(m-5) 0.5891947149681041048896399e-1 * c(m-4) + 0.1858378996391679448655070e-1 * c(m-3) + 0.7240905383565181316381731e-2 * c(m-2) + 0.2349927974590068869356781e-1 * c(m) - 0.4046360079256766884300687e-1 * c(m-6) + 0.1223513270418807666970488e0 * c(m-5) -0.2404661162020836566908542e-1 * c(m-4) - 0.7348845587775519698437916e-2 * c(m-3) - 0.8105784530576404277872603e-3 * c(m-2) + 0.9574633163221758060736592e-2 * c(m-1) - 0.1828896813877197352675410e-1 * c(m) + 0.1350326632905990039353503e-1 * c(m-6) - 0.1315967038382618382356495e-1 * c(m-5);
+            0.5522702088127090209264064e-3 * c(m-7) - 0.3265435411305071914756373e-2 * c(m-6) + 0.7462059484530855073291365e-2 * c(m-5) - 0.4748894282038492179461399e-2 * c(m-4) 0.5528052133944605740009217e-1 * c(m-6) - 0.8631683980217122275970376e-1 * c(m-5) - 0.3276463639080639163926118e-1 * c(m-7) + 0.5268984374242044588776166e-1 * c(m-4) 0.5331362125287625412555844e-1 * c(m-7) + 0.1736073411355428563685818e0 * c(m-5) + 0.8671038084174692625075159e-2 * c(m-3) + 0.8084259844422177692569663e-1 * c(m-6) - 0.1664345989168155800449120e0 * c(m-4) -0.2720908083525083608370563e-1 * c(m-7) - 0.1931148612480615118957263e0 * c(m-6) - 0.3332941113251635390801278e-1 * c(m-3) + 0.2605582646183255957264249e-3 * c(m-2) + 0.1432116665752147607469646e-2 * c(m-1) + 0.1207544072304193806052558e-2 * c(m) - 0.1348436986667115543203552e1 * c(m-5) + 0.1687723507780044227927853e-1 * c(m-4) 0.6107825764368264576481962e-2 * c(m-7) + 0.1155752633643216628010304e0 * c(m-6) + 0.2096413329579026439044119e1 * c(m-5) + 0.3357721707576477199985656e0 * c(m-3) + 0.3291545083271862858501887e-3 * c(m-2) + 0.6641183499427826101618457e-2 * c(m-1) + 0.3449455095910233625229891e-2 * c(m) + 0.8270696421223286922584620e0 * c(m-4) -0.4995827370863505253765970e-1 * c(m-6) - 0.1263507837371824205693950e1 * c(m-5) - 0.8712928907711754187084757e-2 * c(m-2) - 0.2487040599390160764166412e-1 * c(m-1) - 0.1486895819265604128572498e-1 * c(m) - 0.1726565392121567634950213e1 * c(m-4) 0.5402985338373433052255418e0 * c(m-5) - 0.1979290298620869974478871e0 * c(m-3) - 0.2760353365637712827793337e-1 * c(m-1) - 0.4671751091575462868310238e-2 * c(m) - 0.6952587985456154591014641e-1 * c(m-6) + 0.1571507277911208446562686e1 * c(m-4) -0.1319358558853174530078498e0 * c(m-5) - 0.1872196143003808021730728e0 * c(m-3) + 0.9147192682075630179962131e-2 * c(m-2) + 0.6712774475803763988977355e-1 * c(m) + 0.9630407686703666967100804e-1 * c(m-6) - 0.6882132817757726722141421e0 * c(m-4) 0.1241625568998496895352046e-1 * c(m-5) + 0.7403484645316174090533193e-1 * c(m-3) - 0.1023976547309387874453988e-2 * c(m-2) + 0.4440063948509876221050939e-1 * c(m-1) - 0.5224403464202056316702078e-1 * c(m) - 0.3213800979246298453953842e-1 * c(m-6) + 0.1178181682424363524005403e0 * c(m-4);
+            0.6272075574042975468177820e-3 * c(m-6) - 0.1200429618441003833696998e-1 * c(m-5) + 0.1137708862700574079015220e-1 * c(m-4) -0.5373770512016897565958305e-2 * c(m-6) + 0.1453421858063658498587377e0 * c(m-5) - 0.1399684152943489522927794e0 * c(m-4) -0.5013247356072127938999311e0 * c(m-5) + 0.5021853752328231128475915e0 * c(m-4) - 0.1197175073672143005877150e-1 * c(m-6) 0.3590669644811151307464697e-1 * c(m-6) - 0.5925443480724830632401754e0 * c(m-4) - 0.6897142765790609546343709e-2 * c(m-2) - 0.5363098747528542488971874e-2 * c(m-1) - 0.5205147429855955657625694e-2 * c(m) + 0.9977064356292750529201981e0 * c(m-5) -0.4995827370863505253765970e-1 * c(m-6) - 0.1263507837371824205693950e1 * c(m-5) - 0.8712928907711754187084757e-2 * c(m-2) - 0.2487040599390160764166412e-1 * c(m-1) - 0.1486895819265604128572498e-1 * c(m) - 0.1726565392121567634950213e1 * c(m-4) 0.2760393423824887721078848e-1 * c(m-6) + 0.1190550338687608873798462e1 * c(m-5) + 0.4253084328734353394994388e1 * c(m-4) + 0.2306367624634749229113646e0 * c(m-2) + 0.9313657638804699948929701e-1 * c(m-1) + 0.6409299775987186986730499e-1 * c(m) -0.8755807343482262259774782e0 * c(m-5) - 0.3645285178085761821545207e1 * c(m-4) + 0.1033717994630886401730470e0 * c(m-1) + 0.2013769413884797246646959e-1 * c(m) + 0.4106783858513785463625543e-1 * c(m-6) 0.3956598149904136332753521e0 * c(m-5) + 0.1630560443616104907615866e1 * c(m-4) - 0.2421320004064592721552708e0 * c(m-2) - 0.2893557395653431666593814e0 * c(m) - 0.5688529641249387985434413e-1 * c(m-6) -0.7684117160199014594442072e-1 * c(m-5) - 0.2928439026361256842196229e0 * c(m-4) + 0.2710530961648671297733465e-1 * c(m-2) - 0.1662748711097054895317080e0 * c(m-1) + 0.2251991532891353212689574e0 * c(m) + 0.1898341454096471754822498e-1 * c(m-6);
+            0.9209089963443799485648361e-2 * c(m-5) - 0.3129629392354775191148163e-3 * c(m-6) - 0.8896127024208321966533544e-2 * c(m-4) -0.1059816030196818445908057e0 * c(m-5) + 0.1014880675788250237247178e0 * c(m-4) + 0.4493535440856820866087846e-2 * c(m-6) 0.3328335104489738933610597e0 * c(m-5) - 0.3179803804558436283847901e0 * c(m-4) - 0.5111353189352474549563559e-2 * c(m-3) - 0.9741776803777790426705996e-2 * c(m-6) 0.7272438906214475928744770e-1 * c(m-4) + 0.1964682777744275219350831e-1 * c(m-3) - 0.5952475275883259619711594e-2 * c(m-1) - 0.1635430866921887819487473e-2 * c(m) + 0.2921234010758621482958052e-1 * c(m-6) - 0.4659516693228870973898560e0 * c(m-5) 0.5402985338373433052255418e0 * c(m-5) - 0.1979290298620869974478871e0 * c(m-3) - 0.2760353365637712827793337e-1 * c(m-1) - 0.4671751091575462868310238e-2 * c(m) - 0.6952587985456154591014641e-1 * c(m-6) + 0.1571507277911208446562686e1 * c(m-4) -0.8755807343482262259774782e0 * c(m-5) - 0.3645285178085761821545207e1 * c(m-4) + 0.1033717994630886401730470e0 * c(m-1) + 0.2013769413884797246646959e-1 * c(m) + 0.4106783858513785463625543e-1 * c(m-6) 0.1070920689960817104203947e1 * c(m-5) + 0.3717418466925056542408153e1 * c(m-4) + 0.1166740554279680007487795e0 * c(m-3) + 0.1147318200715868527529827e0 * c(m-1) + 0.6327161147136873807796515e-2 * c(m) + 0.6235373239336055200426697e-1 * c(m-6) -0.6639605248735044787146222e0 * c(m-5) - 0.1865625445986772763641423e1 * c(m-4) + 0.1103611313171476425250639e0 * c(m-3) - 0.9091410269992464604926176e-1 * c(m) - 0.8636954541126674177407762e-1 * c(m-6) 0.1582127073537215443965653e0 * c(m-5) + 0.3746489300753517635549495e0 * c(m-4) - 0.4364163147111892346990101e-1 * c(m-3) - 0.1845476106024151050283847e0 * c(m-1) + 0.7075642937243715046279337e-1 * c(m) + 0.2882271848190011329385407e-1 * c(m-6);
+            -0.3576545132696983143406173e-2 * c(m-5) + 0.4335019854436220306755673e-3 * c(m-6) + 0.3143043147253361112730605e-2 * c(m-4) 0.4093499466767054661591066e-1 * c(m-5) - 0.3471075437892810033585296e-1 * c(m-4) - 0.6224240288742446280057699e-2 * c(m-6) -0.1080774142196007991746827e0 * c(m-5) + 0.9941834083648937298100811e-1 * c(m-4) - 0.4834791406446907590553793e-2 * c(m-3) + 0.1349386478955833378422842e-1 * c(m-6) 0.5891947149681041048896399e-1 * c(m-4) + 0.1858378996391679448655070e-1 * c(m-3) + 0.7240905383565181316381731e-2 * c(m-2) + 0.2349927974590068869356781e-1 * c(m) - 0.4046360079256766884300687e-1 * c(m-6) + 0.1223513270418807666970488e0 * c(m-5) -0.1319358558853174530078498e0 * c(m-5) - 0.1872196143003808021730728e0 * c(m-3) + 0.9147192682075630179962131e-2 * c(m-2) + 0.6712774475803763988977355e-1 * c(m) + 0.9630407686703666967100804e-1 * c(m-6) - 0.6882132817757726722141421e0 * c(m-4) 0.3956598149904136332753521e0 * c(m-5) + 0.1630560443616104907615866e1 * c(m-4) - 0.2421320004064592721552708e0 * c(m-2) - 0.2893557395653431666593814e0 * c(m) - 0.5688529641249387985434413e-1 * c(m-6) -0.6639605248735044787146222e0 * c(m-5) - 0.1865625445986772763641423e1 * c(m-4) + 0.1103611313171476425250639e0 * c(m-3) - 0.9091410269992464604926176e-1 * c(m) - 0.8636954541126674177407762e-1 * c(m-6) 0.4681819359722749441073885e0 * c(m-5) + 0.1015239189167790053447110e1 * c(m-4) + 0.1043897828092562609502636e0 * c(m-3) + 0.2542001760457345743492403e0 * c(m-2) + 0.1306332157111667628555907e1 * c(m) + 0.1196351539550049336518187e0 * c(m-6) -0.1195777325611201766551392e0 * c(m-5) - 0.2187310061229745694542609e0 * c(m-4) - 0.4128029838349298819825156e-1 * c(m-3) - 0.2845627370491611369031341e-1 * c(m-2) - 0.1016689339350338144430605e1 * c(m) - 0.3992391469197282238624438e-1 * c(m-6);
+            0.5593983696629863059347067e-3 * c(m-5) - 0.1446656414398166805849327e-3 * c(m-6) - 0.4147327282231696253497740e-3 * c(m-4) -0.6486184157331537899459796e-2 * c(m-5) + 0.4409068609809831485979484e-2 * c(m-4) + 0.2077115547521706413480312e-2 * c(m-6) 0.1319674981073749167009902e-1 * c(m-5) - 0.1060554802883657391328704e-1 * c(m-4) + 0.1911888563316170927411831e-2 * c(m-3) - 0.4503090345217088684223814e-2 * c(m-6) -0.2404661162020836566908542e-1 * c(m-4) - 0.7348845587775519698437916e-2 * c(m-3) - 0.8105784530576404277872603e-3 * c(m-2) + 0.9574633163221758060736592e-2 * c(m-1) - 0.1828896813877197352675410e-1 * c(m) + 0.1350326632905990039353503e-1 * c(m-6) - 0.1315967038382618382356495e-1 * c(m-5) 0.1241625568998496895352046e-1 * c(m-5) + 0.7403484645316174090533193e-1 * c(m-3) - 0.1023976547309387874453988e-2 * c(m-2) + 0.4440063948509876221050939e-1 * c(m-1) - 0.5224403464202056316702078e-1 * c(m) - 0.3213800979246298453953842e-1 * c(m-6) + 0.1178181682424363524005403e0 * c(m-4) -0.7684117160199014594442072e-1 * c(m-5) - 0.2928439026361256842196229e0 * c(m-4) + 0.2710530961648671297733465e-1 * c(m-2) - 0.1662748711097054895317080e0 * c(m-1) + 0.2251991532891353212689574e0 * c(m) + 0.1898341454096471754822498e-1 * c(m-6) 0.1582127073537215443965653e0 * c(m-5) + 0.3746489300753517635549495e0 * c(m-4) - 0.4364163147111892346990101e-1 * c(m-3) - 0.1845476106024151050283847e0 * c(m-1) + 0.7075642937243715046279337e-1 * c(m) + 0.2882271848190011329385407e-1 * c(m-6) -0.1195777325611201766551392e0 * c(m-5) - 0.2187310061229745694542609e0 * c(m-4) - 0.4128029838349298819825156e-1 * c(m-3) - 0.2845627370491611369031341e-1 * c(m-2) - 0.1016689339350338144430605e1 * c(m) - 0.3992391469197282238624438e-1 * c(m-6) 0.3167964748016105299646518e-1 * c(m-5) + 0.4976563420877041544013670e-1 * c(m-4) + 0.1632404042590951953384672e-1 * c(m-3) + 0.3185519088796429015220016e-2 * c(m-2) + 0.2968472090638000742888467e0 * c(m-1) + 0.7912667594695582093926295e0 * c(m) + 0.1332316557164627464149716e-1 * c(m-6);
+        ];
+
+        M(5,10)=M(10,5);
+        M(m-4,m-9)=M(m-9,m-4);
+
+        M=M/h;
+        D2 = HI*(-M - c(1)*e_l*d1_l' + c(m)*e_r*d1_r');
+    end
+    D2 = @D2_fun;
+
+    % Fourth derivative, 1th order accurate at first 8 boundary points (still
+    % yield 5th order convergence if stable: for example u_tt=-u_xxxx
+    stencil = [7/240, -2/5, 169/60, -122/15, 91/8, -122/15, 169/60, -2/5, 7/240];
+    diags = -4:4;
+    M4 = stripeMatrix(stencil, diags, m);
+
+    M4_U = [
+        0.1394226315049e13/0.367201486080e12 -0.1137054563243e13/0.114750464400e12 0.16614189027367e14/0.1836007430400e13 -0.1104821700277e13/0.306001238400e12 0.1355771086763e13/0.1836007430400e13 -0.27818686453e11/0.459001857600e12 -0.40671054239e11/0.1836007430400e13 0.5442887371e10/0.306001238400e12;
+        -0.1137054563243e13/0.114750464400e12 0.70616795535409e14/0.2570410402560e13 -0.173266854731041e15/0.6426026006400e13 0.28938615291031e14/0.2570410402560e13 -0.146167361863e12/0.71400288960e11 0.2793470836571e13/0.12852052012800e14 0.6219558097e10/0.428401733760e12 -0.7313844559e10/0.166909766400e12;
+        0.16614189027367e14/0.1836007430400e13 -0.173266854731041e15/0.6426026006400e13 0.378613061504779e15/0.12852052012800e14 -0.9117069604217e13/0.642602600640e12 0.632177582849e12/0.233673672960e12 -0.1057776382577e13/0.6426026006400e13 0.443019868399e12/0.4284017337600e13 -0.3707981e7/0.2318191200e10;
+        -0.1104821700277e13/0.306001238400e12 0.28938615291031e14/0.2570410402560e13 -0.9117069604217e13/0.642602600640e12 0.5029150721885e13/0.514082080512e12 -0.5209119714341e13/0.1285205201280e13 0.12235427457469e14/0.12852052012800e14 -0.13731270505e11/0.64260260064e11 0.2933596129e10/0.40800165120e11;
+        0.1355771086763e13/0.1836007430400e13 -0.146167361863e12/0.71400288960e11 0.632177582849e12/0.233673672960e12 -0.5209119714341e13/0.1285205201280e13 0.14871726798559e14/0.2570410402560e13 -0.7504337615347e13/0.1606506501600e13 0.310830296467e12/0.171360693504e12 -0.55284274391e11/0.183600743040e12;
+        -0.27818686453e11/0.459001857600e12 0.2793470836571e13/0.12852052012800e14 -0.1057776382577e13/0.6426026006400e13 0.12235427457469e14/0.12852052012800e14 -0.7504337615347e13/0.1606506501600e13 0.106318657014853e15/0.12852052012800e14 -0.14432772918527e14/0.2142008668800e13 0.58102695589e11/0.22666758400e11;
+        -0.40671054239e11/0.1836007430400e13 0.6219558097e10/0.428401733760e12 0.443019868399e12/0.4284017337600e13 -0.13731270505e11/0.64260260064e11 0.310830296467e12/0.171360693504e12 -0.14432772918527e14/0.2142008668800e13 0.27102479467823e14/0.2570410402560e13 -0.1216032192203e13/0.153000619200e12;
+        0.5442887371e10/0.306001238400e12 -0.7313844559e10/0.166909766400e12 -0.3707981e7/0.2318191200e10 0.2933596129e10/0.40800165120e11 -0.55284274391e11/0.183600743040e12 0.58102695589e11/0.22666758400e11 -0.1216032192203e13/0.153000619200e12 0.20799922829107e14/0.1836007430400e13;
+    ];
+
+    M4(1:8,1:8) = M4_U;
+    M4(m-7:m,m-7:m) = rot90(  M4_U ,2 );
+    M4 = M4/h^3;
+
+
+
+    D4=HI*(M4 - e_l*d3_l'+e_r*d3_r' + d1_l*d2_l'-d1_r*d2_r');
+end
diff -r a0d615bde7f8 -r 49e3870335ef +sbp/D2VariableCompatibleHollow.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/+sbp/D2VariableCompatibleHollow.m	Sat Jul 11 06:54:15 2020 -0700
@@ -0,0 +1,81 @@
+classdef D2VariableCompatibleHollow < sbp.OpSet
+    properties
+        D1 % SBP operator approximating first derivative
+        H % Norm matrix
+        HI % H^-1
+        Q % Skew-symmetric matrix
+        e_l % Left boundary operator
+        e_r % Right boundary operator
+        D2 % SBP operator for second derivative
+        M % Norm matrix, second derivative
+        d1_l % Left boundary first derivative
+        d1_r % Right boundary first derivative
+        m % Number of grid points.
+        h % Step size
+        x % grid
+        borrowing % Struct with borrowing limits for different norm matrices
+    end
+
+    methods
+        function obj = D2VariableCompatibleHollow(m,lim,order)
+
+            x_l = lim{1};
+            x_r = lim{2};
+            L = x_r-x_l;
+            obj.h = L/(m-1);
+            obj.x = linspace(x_l,x_r,m)';
+
+            switch order
+
+                case 6
+
+                    [obj.H, obj.HI, obj.D1, D2, ...
+                    ~, obj.e_l, obj.e_r, ~, ~, ~, ~, ~,...
+                     d1_l, d1_r] = ...
+                        sbp.implementations.d4_variable_hollow_6(m, obj.h);
+
+                case 4
+                    [obj.H, obj.HI, obj.D1, D2, obj.e_l,...
+                        obj.e_r, d1_l, d1_r] = ...
+                        sbp.implementations.d2_variable_hollow_4(m,obj.h);
+                case 2
+                    [obj.H, obj.HI, obj.D1, D2, obj.e_l,...
+                        obj.e_r, d1_l, d1_r] = ...
+                        sbp.implementations.d2_variable_hollow_2(m,obj.h);
+
+                otherwise
+                    error('Invalid operator order %d.',order);
+            end
+            obj.borrowing.H11 = obj.H(1,1)/obj.h; % First element in H/h,
+            obj.borrowing.M.d1 = obj.H(1,1)/obj.h; % First element in H/h is borrowing also for M
+            obj.borrowing.R.delta_D = inf;
+            obj.m = m;
+            obj.M = [];
+
+
+            D1 = obj.D1;
+            e_r = obj.e_r;
+            e_l = obj.e_l;
+
+            % D2 = Hinv * (-M + br*er*d1r^T - bl*el*d1l^T);
+            % Replace d1' by e'*D1 in D2.
+            D2_compatible = @(b) D2(b) - obj.HI*(b(m)*e_r*d1_r' - b(m)*e_r*e_r'*D1) ...
+                                       + obj.HI*(b(1)*e_l*d1_l' - b(1)*e_l*e_l'*D1);
+
+            obj.D2 = D2_compatible;
+            obj.d1_l = (e_l'*D1)';
+            obj.d1_r = (e_r'*D1)';
+
+        end
+        function str = string(obj)
+            str = [class(obj) '_' num2str(obj.order)];
+        end
+    end
+
+
+end
+
+
+
+
+
diff -r a0d615bde7f8 -r 49e3870335ef +scheme/Elastic2dVariableAnisotropic.m
--- a/+scheme/Elastic2dVariableAnisotropic.m	Fri Jul 10 20:24:23 2020 -0700
+++ b/+scheme/Elastic2dVariableAnisotropic.m	Sat Jul 11 06:54:15 2020 -0700
@@ -107,10 +107,14 @@
 
             % 1D operators
             ops = cell(dim,1);
+            opsHollow = cell(dim,1);
             h = zeros(dim,1);
             for i = 1:dim
                 ops{i} = opSet{i}(m(i), lim{i}, order);
                 h(i) = ops{i}.h;
+                if hollow
+                    opsHollow{i} = sbp.D2VariableCompatibleHollow(m(i), lim{i}, order);
+                end
             end
 
             % Borrowing constants
@@ -121,6 +125,7 @@
             I = cell(dim,1);
             D1 = cell(dim,1);
             D2 = cell(dim,1);
+            D2Hollow = cell(dim,1);
             H = cell(dim,1);
             Hi = cell(dim,1);
             e_0 = cell(dim,1);
@@ -131,6 +136,9 @@
             for i = 1:dim
                 I{i} = speye(m(i));
                 D1{i} = ops{i}.D1;
+                if hollow
+                    D2Hollow{i} = opsHollow{i}.D2;
+                end
                 D2{i} = ops{i}.D2;
                 H{i} =  ops{i}.H;
                 Hi{i} = ops{i}.HI;
@@ -231,9 +239,10 @@
                 for j = 1:dim
                     for l = 1:dim
                         coeff = C{k,j,k,l};
-                        D_kk = D2{1}(coeff(p));
                         if hollow && r > nBP && r < m(2) - nBP + 1
-                            D_kk = mask*D_kk;
+                            D_kk = D2Hollow{1}(coeff(p));
+                        else
+                            D_kk = D2{1}(coeff(p));
                         end
                         D2_temp{j,k,l}(p,p) = D_kk;
                     end
@@ -253,9 +262,10 @@
                 for j = 1:dim
                     for l = 1:dim
                         coeff = C{k,j,k,l};
-                        D_kk = D2{2}(coeff(p));
                         if hollow && r > nBP && r < m(1) - nBP + 1
-                            D_kk = mask*D_kk;
+                            D_kk = D2Hollow{2}(coeff(p));
+                        else
+                            D_kk = D2{2}(coeff(p));
                         end
                         D2_temp{j,k,l}(p,p) = D_kk;
                     end
@@ -292,8 +302,6 @@
             if hollow
                 mask = maskX + maskY;
                 mask = mask>0;
-
-                % D = maskX*maskY*D;
                 D = mask*D;
             end
             D = obj.RHOi_kron*D;