y=0:100:4500000;
u0=9.12;
v=(1/u0).*y;
x=v.^.2;
t0=clock;
p=gammainc(x,5);
i=-.5.*p+.5;
durata1=etime(clock,t0);
t2=clock;
%z=y.^.2;
gg=[1/48 1/12 1/4 1/2 1/2];
gh=polyval(gg,x);
gb=gh.*exp(-x);
durata2=etime(clock,t2);