How do you plot a graph when using a while loop?

When I run this code, I get a blank graph. How would I fix the code so that I would be able to see the actual graphed data?

V0=100;
G=9.8;
theta=pi/4;
T=-0.01;
while (T<=20)
    T=T+0.01;
    HT=T*V0*cos(theta);
end
plot(T,HT);
title('horizontal path');
xlabel('time(s)');
ylabel('distance(m)');

Answer 1

[David Hill]

V0=100;
G=9.8;
theta=pi/4;
T(1)=-0.01;
c=0;
while (T<=20)
    c=c+1;
    T(c+1)=T(c)+0.01;
    HT(c)=T(c+1)*V0*cos(theta);
end
plot(T(2:end),HT);
title('horizontal path');
xlabel('time(s)');
ylabel('distance(m)');

Much easier without a loop.