94 lines
1.4 KiB
Mathematica
94 lines
1.4 KiB
Mathematica
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%% eulero forward DIrichlet
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L=pi;
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T=2;
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f=@(x,t) 0*x.*t;
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c1=@(t) 1+0*t;
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c2=@(t) 0*t;
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u0=@(x) 0*x;
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D=0.5;
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%uex=@(x,t) cos(x).*exp(t);
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N=10;
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K=200;
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[x,t,u]=Dirichlet_EA(L,N,T,K,c1,c2,f,u0,D);
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figure(1)
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for ii=1:K+1
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plot(x,u(:,ii)');
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xlim([0 L])
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pause(0.05);
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end
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space=linspace(0,L,101);
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time=linspace(0,T,201);
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[xx,yy]=meshgrid(time,space);
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%exsol=uex(yy,xx);
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figure(2)
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mesh(t,x,u)
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%figure(2)
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%mesh(xx,yy,exsol)
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%% Eulero forward Mixed BC
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L=2*pi;
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T=5;
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f=@(x,t) 0*x.*t;
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c1=@(t) 1+0*t;
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c2=0;
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u0=@(x) 0*x;
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D=1.1;
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%uex=@(x,t) cos(x).*exp(t);
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N=25;
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K=200;
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[x,t,u]=Mixed_EA(L,N,T,K,c1,c2,f,u0,D);
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figure(1)
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for ii=1:K+1
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plot(x,u(:,ii)');
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xlim([0 L])
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ylim([0 1.5])
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pause(0.02);
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end
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space=linspace(0,L,101);
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time=linspace(0,T,201);
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[xx,yy]=meshgrid(time,space);
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%exsol=uex(yy,xx);
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figure(2)
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mesh(t,x,u)
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%figure(2)
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%mesh(xx,yy,exsol)
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%% Eulero Backward Mixed BC
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L=2*pi;
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T=5;
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f=@(x,t) 0*x.*t;
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c1=@(t) 1+0*t;
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c2=0;
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u0=@(x) 0*x;
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D=1;
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%uex=@(x,t) cos(x).*exp(t);
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N=25;
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K=200;
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[x,t,u]=Mixed_EI(L,N,T,K,c1,c2,f,u0,D);
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figure(1)
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for ii=1:K+1
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plot(x,u(:,ii)');
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xlim([0 L])
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ylim([0 1.5])
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pause(0.02);
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end
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space=linspace(0,L,101);
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time=linspace(0,T,201);
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[xx,yy]=meshgrid(time,space);
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%exsol=uex(yy,xx);
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figure(2)
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mesh(t,x,u)
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%figure(2)
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%mesh(xx,yy,exsol)
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