MATLAB: Matlab code from literature gives errors

findMATLABmatrix

have this code from a book I recently looked at, I want to implement the code but I get loads of errors , can someone help me localize the errors or possibly make a runnable example?
function [P,b]=AmericanPrice(r,delta,sigma,K,nx,nt, Xhat,That)
%Usage:P=AmericanPrice(r,delta,sigma,K,nx,nt,Xhat,That) 
%Example:P=AmericanPrice(0.08,0.12,.2,100,50,10,300,3)
dx=Xhat/nx; 
dt=That/nt; 
for i=1:nx-1 
    A(i,i:i+2)=[((r-delta)*dt*i-sigmaˆ2*dt*iˆ2)/2... 
        1+r*dt+sigmaˆ2*dt*iˆ2 
        (-(r-delta)*dt*i-sigmaˆ2*dt*iˆ2)/2]; 
end
P(:,1)=max(K-[0:dx:Xhat],0);
if(delta==0) 
    b(1)=K; 
else
    b(1)=min(K,K*r/delta);
end
for j=2:nt+1 
    bn=0; run=1; 
    while(run) 
        An=[A(1+bn:end,1+bn:end)]; 
        An(end+1,end-1:end)=[-1 1]; 
        An(end+1,1)=1; 
        Cn=[P(bn+2:nx,j-1)’ 0 K-bn*dx]’; 
        Pn=inv(An)*Cn; 
        if(Pn(2)$<$K-((bn+1)*dx)) 
            bn=find(sign(diff(Pn)/dx+1)-1,1,{’last’})+bn; 
        else
            b(j)=bn*dx; run=0; 
        end
    end
    P(:,j)=[K-[0:bn-1]*dx Pn’]; 
end
what i have done so far: i changed the sigmaˆ2 to sigma*sigma, same thing with i. Then i replaced the ’ with '. I did not know what to d o with "…" The error i get is
Undefined function 'find' for input arguments of type 'cell'.
Error in FDM (line 28)
            bn=find(sign(diff(Pn)/dx+1)-1,1,{'last'})+bn;

Best Answer

Change
              bn=find(sign(diff(Pn)/dx+1)-1,1,{’last’})+bn;
to
              bn=find(sign(diff(Pn)/dx+1)-1,1,’last’)+bn;
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