fminsearch error.

Hi, I have built this function

function [ out ] = K_S( par,P) %UNTITLED3 Summary of this function goes here

% Detailed explanation goes here

T=rows(P);

m=par(1,1);

r=par(1,2);

F=par(1,3);

mu0=par(1,4);

sigma0=par(1,5);

alpha=1/(m-1);

M=mu0/alpha;

V=(sigma0/alpha)^2;

for t=1:T

W(t,1)=(P(t,1).*exp(-r*t)-F).^-(m-1); V=(sigma0/alpha)^2;

end dW=W(2:end,1)-W(1:end-1,1); x=sort(dW); cdfvals=cdf('norm',x,M,sqrt(V)); n=length(x); S=(1:n)'/n; %size=size/2;

d=max(abs(cdfvals-S)); %statistic=d; %KS=kolmogorov(dW,0.05,'normcdf',M,sqrt(V));

out=d;

that I should minimize to find the parameters par. par is a vector 1*5.

For that I used fminsearch : [param]=fminsearch(@(par) K_S(par,P),par0);

but it returns a bunch of errors: *??? Error using ==> erfcore Input must be real.

Error in ==> erfc at 23 y = erfcore(x,1);

Error in ==> normcdf at 68 p = 0.5 * erfc(-z ./ sqrt(2));

Error in ==> cdf at 105 p = normcdf(x,a1,a2);

Error in ==> K_S at 24 cdfvals=cdf('norm',x,M,sqrt(V));

Error in ==> @(par)K_S(par,P)

Error in ==> fminsearch at 265 x(:) = y; f = funfcn(x,varargin{:});

I don't understsand why it returns error in the function K_S, since it works perfectly when iI uuse it normally.

There is someone who can help me ??

thanks Gaia