Extending the lines is straightforward.
What region do you want to shade? I created patch objects for all of them, so choose the ones you want. You can turn off the edges of the patch objects wiby adding 'EdgeColor','none' to their arguments.
clear all
W=45000;
S=9;
b=7.5;
clmax=2;
clmin=-1;
nmax=4;
AR=7;
nmin=-3;
clalpha = 2*pi;
Vdive=290;
Vstall=sqrt(2*W/(1.225*S*clmax));
cd0 = 0.005;
k = 1/pi/AR;
n1v = 0:0.25:4;
i=0;
for n1 = 0:0.25:4
i=i+1;
V(i) = sqrt(2*n1*W/1.225/S/clmax);
nmaxx(i)=nmax;
nminn(i)=nmin;
end
j=0;
n2v = -3:0.25:0;
for n2 = -3:0.25:0
j=j+1;
V2(j) = sqrt(2*n2*W/1.225/S/clmin);
nmaxx(j)=nmax;
nminn(j)=nmin;
end
k=0;
nv=-3:0.25:4;
for n=-3:0.25:4
k=k+1;
Vmax(k)=Vdive;
end
figure(5); plot(V,n1v, 'DisplayName','n1v')
hold on
plot([V Vmax(end)],[nmaxx nmaxx(end)], 'DisplayName','nmaxx')
hold on
plot([V Vmax(end)],[nminn nminn(end)], 'DisplayName','nminn')
hold on
plot(V2,n2v, 'DisplayName','n2v');
plot(Vmax,nv, 'DisplayName','nv');
xlim([-1 400]);
ylim([-5 5]);
patch([Vmax(end) V2 flip(V2) Vmax(end)], [zeros(size([n2v n2v(1)])) flip(n2v) n2v(1)], 'm', 'FaceAlpha',0.25)
patch([V Vmax(end) Vmax(end) flip(V)], [zeros(size([n1v n1v(end)])) n1v(end) flip(n1v)], 'c', 'FaceAlpha',0.25)
patch([V2 flip(V2)], [ones(size(n2v))*min(n2v) flip(n2v)], 'g', 'FaceAlpha',0.25)
patch([V flip(V)], [n1v ones(size(n1v))*max(n1v)], [0.8 0.4 0.2], 'FaceAlpha',0.25)
The patch pbjects were a bit of a challenge because the vectors creating them were not as I expected them to be. You can identify them by their colours.
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