memo

angle = 0:1/1000:90;
s1 = cos(angle).^2 .* cos(3*angle).^2;
s2 = sin(angle);
s3 = sin(angle).^2;
polar(angle,s1)
hold on
polar(angle,s2)
polar(angle,s3)
hpbw1 = rad2deg(acos(0.707./cos(3*angle)));
mina = min (find(imag(hpbw1) > 0));
s1(mina:end) = [];
s1 (find (s1-0.5 < 0 ))=[];
s1_hpbw1 = hpbw1(length(s1))

s2_hpbw = rad2deg(asin(max(s2)/2))
s3_hpbw = rad2deg(asin(sqrt(max(s3)/2)))