matlab indexing issue with range -pi:pi

I have following code, which i need to plot for alpha versus theta.

But i am unable to index it properly.

Kindly help. Thanks in anticipation. Regards

amin=0.2;

for theta=-3.1416:1.5708:3.1416 (-pi:pi/2:pi)

for gamma=0:0.5:3

phi=amin-(-pi/2);

alpha((?),(gamma*2)+1)=(1-amin)*(((sin(theta-phi)+1)/2).^gamma)+amin;

end

end

Answer 1

[VBBV]

amin=0.2;
theta = -pi:pi/2:pi;
gamma=0:0.5:3;
for T=1:length(theta)
    for G = 1:length(gamma)
        phi=amin-(-pi/2);
        alpha(T,G)=((1-amin)*(((sin(theta(T)-phi)+1)/2).^gamma(G))+amin)/((gamma(G)*2)+1);
    end
end
plot(theta,alpha)
xlabel('theta');ylabel('alpha')

[Chetan Fadnis]

Thank you,

But the maximum values i.e. at -pi and at pi should be 1.

and what will be the case, if amin is also variable between 0 and 1.

[Walter Roberson]

The maximum value is 1 exactly and it is being plotted. You need to ylim([0 1.1])