i got this code over the interent, its for the TIAN binomial model

% File: TIAN1.m

% Objective: Binomial pricing of "at-the-money" american put

%option using TIAN binomial model

% Author: Group 4

S0=40;

K=40;

T= 5/12;

r= 0.08;

sigma = 0.30;

price=1:250;

for n=25:250

deltat=T/n;

M=exp(r*deltat);

V=exp(sigma^2*deltat);

s=sqrt(V^2+2*V-3);

u=M*V*(V+1+s)/2;

d=M*V*(V+1-s)/2;

p=(M-d)/(u-d);

beta=1/M;

V=pric(S0,K,u,d,p,beta,n);

price(n)=V(1,1);

end

plot(25:250,price(25:250));

xlabel('Iterations');

ylabel('Option Value');

title('Binomial Pricing');

its giving me error

Error in ==> TIAN2 at 20

V=pric(S0,K,u,d,p,beta,n);

the problem is with the "pric" function, because its not like "binprice" you can use in matlab, it is self made. i got in touch with the guy who posted this code and he doesnt even have it, as he posted it around 2006. Anywaz i was wondering if any one could help me on this. any suggestions or ideas wil be appriciated. Thank you