MATLAB: The data is not plotting the graph using plot(Q,h)

Question

Hi,

I am not sure what is happening here? I am using the code below and all working fine but whenever it supposed to plot the graph it is not plotting the graph instead it is just printing all the values in command line section. So, I am using plot (Q,h) but whenever, i used scatter (Q,h) it put the points on the graph but for data representations I will need to plot the curves rather then scatter points.

I even used this code to join the scatter points but no result.

Code 2:

scatter(Q,h,'.','LineWidth',1);
   line(Q,h,'Color','k','LineStyle','-','LineWidth',5)
    hold on

Code1:

for Q = [0:1:100];
    if h < h1
        v_2 = ((Q/1000) / Area_Outlet1)
        
        h = ((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 = h1 + ((1 / (rho * g)) * (Patm2 - Patm1 + 0.5 * rho * (v_2a^2 - v_1^2)) + h_f)*1000
    
    end
    plot (Q,h)
end

Any Help?

Answer 1

q = [0:1:100];
h = zeros(size(q)) ; 
for Q = 1:length(q)
    if val < h1     % < --- think of this line 
        v_2 = ((Q/1000) / Area_Outlet1)
        
        h(Q) = ((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(Q) = h1 + ((1 / (rho * g)) * (Patm2 - Patm1 + 0.5 * rho * (v_2a^2 - v_1^2)) + h_f)*1000
    
    end   
end
plot (q,h)