function z = simcall(S0,r, sigma, T, K, m)
% repeats plotlogn a total of m times and averages discounted return to the present.
z=[];
hold on
for i=1:m
   z = [z plotlogn(S0, r, sigma, T, K )];
end
optionval=mean(z);
disp([ '  option val= '  num2str(optionval)   ])
hold off