 n=500                                        
x=sqrt(2)*randn(1,n);
for i=1:n
y(i)=x(i)^(-2);
end
z=1:1:n;
plot(z,y)
%e=sum(y);
%f=1/e;
%z=f.*y;
%[l,w]=hist (y,500);
%z=(1/n).*l;
%plot(w,z)
%t=1:1:500;
%plot(t,y)
%t1=0:2:100;
%hist(y,t1)                                                                                                                                                                                                                                                                                                                                                             ;                                                             grid