My code only plots one point

Im trying to plot N(# of stages) vs pi_s(pressure ratio), but i only get one point.

Answer 1

[KALYAN ACHARJYA]

Define Before the loop

t=1:N
for i=1:length(t)
tao_s=
pic_s(i)=
end
plot(t,pic_s);

Also you can avoid the loop here (recomended)

N=.....
tao_s=(Tt1+N.*delta....)./ same . after N, like N.*
pic_s=tao_s.^.....
plot(1:N,pic_s)