How to take the difference of y axis points at the same value of x-axis from 2 curve at the same graph?

Hi,

I am struggling to take a difference between 2 y axis points at the same x axis value from 2 curve.

1st Curve:

x = [20,30,40,50,60,70,80,90,100]

y = [260,350,470,610,625,675,695,750,800]

%Plotting the points on the graph

plot(x,y,'x','LineWidth',3)

line (x,y,'Color','k','LineStyle','--','LineWidth',1)

hold on

2nd Curve:

for i = 2:length(q)

Q = q(i) ;

if h(i-1) < h1

v_2 = ((Q/1000) / Area_Outlet1);

h(i) = 75+((1 / (rho * g)) * (Patm2 - Patm1 + 0.5 * rho * (v_2^2 - v_1^2)) + h_f)*1000

else

v_2a = ((Q/1000) / Area_Outlet2);

h(i) = 75+h1 + ((1 / (rho * g)) * (Patm2 - Patm1 + 0.5 * rho * (v_2a^2 - v_1^2)) + h_f)*1000

end

end

plot(q,h)

hold off

Second curve plotted by using the loop. I want to find out what are the y-axis points at x = [20,30,40,50,60,70,80,90,100] for both curves.

Answer 1

[Ameer Hamza]

You can use interp1()

h_new = interp1(q, h, x); % h_new are values at q=20,30,40,...,100