Sorry for the confusion:


Sheet 9 Solution of Ex 2:

The implementation is for Crank Nicolson.
 
Line 26: b = dt*f(grid(2:end-1)+dt/2);



Sheet 11 solution of Ex 2 (ii)

The convergence rate of the Crank Nicolson scheme is quadratic w.r.t. to the time and the space discretisation.