MATLAB: Plotting two legends on the same plot

plotting

I have trouble plotting two legends for two lines on the same plot . Here are my codes:
p = linspace(0,1,50);
v = -290*9.8*log(0.15+0.85*p);
v2 = -370*9.8*log(0.25+0.75*p);
plot(p,v,'-r');
hold on
legend option1
p2 = plot(p,v2,'-b');
legend option2
hold off
xlabel('PI for two options')
ylabel('staging velocity(km/s)')
When I plot this, only legend option2 shows up. How should I change my codes?

Best Answer

It is easier to first create the lines and then make a single call to legend()
p = linspace(0,1,50);
v = -290*9.8*log(0.15+0.85*p);
v2 = -370*9.8*log(0.25+0.75*p);
plot(p,v,'-r');
hold on
p2 = plot(p,v2,'-b');
legend({'option1', 'option2'})
hold off
xlabel('PI for two options')
ylabel('staging velocity(km/s)')
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