[u1,err1,x,t] = heat1(0,.001,100,50);

r =

  6.0818e-004

flops(0)
[u1,err1,x,t] = heat1(0,.001,100,50);

r =

  6.0818e-004

flops

ans =

       55509

flops(0)
[u,err,x,t] = heat3(0,.001,100,50);

r =

  6.0818e-004

flops

ans =

      817009

817009/55509

ans =

   14.7185

max(max(abs(err)))

ans =

  1.3731e-006

max(max(abs(err1)))

ans =

  1.3631e-006

clear
[u,err,x,t] = heat3(0,.001,10,50);

r =

    0.0061

Error in ==> C:\MATLAB\tri_diag.m
On line 28  ==>   y(j) = rhs(j)-alpha(j)*y(j-1);

Error in ==> C:\MATLAB\periodic_tridiag.m
On line 70  ==> bbi = tri_diag(T,bb);

Error in ==> C:\MATLAB\heat3.m
On line 53  ==>   [u(:,j+1)] = periodic_tridiag(A,u(:,j));

[u,err,x,t] = heat3(0,.01,10,50);

r =

    0.0608

Error in ==> C:\MATLAB\periodic_tridiag.m
On line 64  ==>     T(i,j) = A(i+1,j+1);

Error in ==> C:\MATLAB\heat3.m
On line 53  ==>   [u(:,j+1)] = periodic_tridiag(A,u(:,j));

[u,err,x,t] = heat3(0,.1,10,50);

r =

    0.6082

[u,err,x,t] = heat3(0,.1,20,100);

r =

    1.2413

Error in ==> C:\MATLAB\periodic_tridiag.m
On line 64  ==>     T(i,j) = A(i+1,j+1);

Error in ==> C:\MATLAB\heat3.m
On line 53  ==>   [u(:,j+1)] = periodic_tridiag(A,u(:,j));

[u,err,x,t] = heat3(0,.1,30,100);

r =

    0.8275

[u1,err1,x,t] = heat1(0,.1,30,100);

r =

    0.8275

max(max(abs(err)))

ans =

  1.8076e-004

max(max(abs(err1)))

ans =

  1.2203e-004

plot(x,err1(:,31)); figure(1)
hold on
plot(x,err(:,31),'--'); figure(1)
[u1,err1,x,t] = heat1(0,.2,60,100);

r =

    0.8275

[u,err,x,t] = heat3(0,.2,60,100);

r =

    0.8275

hold off
plot(x,err(:,61),'--'); hold on; plot(x,err1(:,61)); hold off; figure(1)
max(max(abs(err1)))

ans =

  5.7070e+005

max(max(abs(err)))

ans =

  3.2714e-004

diary off