How to output/send data to another function to be used in a calculation

How do i send imported data to Function 2 from function 1 and then send the calculated data in function 2 to function 3 to be used to plot a graph. So basically im trying to link all the function so the work together.

%Function 1

function [time, height]=LagoonInput(Name,birthday)

%Importing Data
Time = importdata('time.txt');
 
%Importing Data
Height = importdata('height.txt');
 
plot(Height,Time)



% Function 2

function [h1,Power]=LagoonProcess(time,height )
%constants
d = 7.2;
al = 11500;
cd = 0.8;
ct = 0.5;
g = 9.807;
p = 1029;
%Area Of turbine = pi*r^2
A = 40.715;

%Variables that need to change after every loop
h1 = 14.05;             %h1 should be replaced with h1New after every 1 loop
h2 = Height(7988:19295,:);  %this data is from a data excel sheet
VFull = 161575;         %VFull should be replaced by NewVolume after every 1 loop 
for c=1:11307          %loop needs to be repeated 16759 times
          
    %Discharge 
   discharge(c) = cd*A*(sqrt(2*g*((abs(h1-h2(c)))))) ;
    V = discharge(c)/A;
     %Power
     Power(c) = (1/2)*ct*p*A*V^3;
      %New Volume Calculation
      NewVolume(c) = VFull - discharge(c);
      VFull=NewVolume(c);
        %New h1
         h1New(c) = ((VFull - discharge(c))/al);
         h1=h1New(c);
end


    
    function []=LagoonProcess(Power,h1New)

%Function 3 

%Power Plot

b = Power(:,1:7644)
z = NewTime;

plot(z,b)

xlabel('Time (s)')
ylabel('Power (W)')
title('Time vs Power')


% Height Plot

h = h1New(1:7644,:)
y = z;

plot(y,h)

xlabel('Time (s)')
ylabel('Height (m)')
title('Time vs Height')



Powertotal= sum(Power)

[Constantinos Yiannakis]

to add, Function 1 is named LagoonInput

function 2 is LagoonProcess

function 3 is LagoonOutput

Answer 1

[Kojiro Saito]

You just need to call functions for passings input/output into/from functions in main script. After saving each function in separate m files, you can call those function in your main script.

For example,

LagoonInput.m

function [time, height] = LagoonInput
    % I'm ommitting input arguments Name and birthday because they're not used
    
    %Importing Data
    time = importdata('time.txt');

    %Importing Data
    height = importdata('height.txt');
end

LagoonProcess.m

function [h1, Power]=LagoonProcess(time, height)
    %constants
    d = 7.2;
    al = 11500;
    cd = 0.8;
    ct = 0.5;
    g = 9.807;
    p = 1029;
    %Area Of turbine = pi*r^2
    A = 40.715;
    %Variables that need to change after every loop
    h1 = 14.05;             %h1 should be replaced with h1New after every 1 loop
    h2 = height(7988:19295,:);  %this data is from a data excel sheet
    VFull = 161575;         %VFull should be replaced by NewVolume after every 1 loop 
    
    % Adding pre allocates for better performance
    discharge = zeros(11307, 1);
    Power = zeros(11307, 1);
    NewVolume = zeros(11307, 1);
    h1New = zeros(11307, 1);
    
    for c=1:11307          %loop needs to be repeated 16759 times

       %Discharge 
       discharge(c) = cd*A*(sqrt(2*g*((abs(h1-h2(c)))))) ;
       V = discharge(c)/A;
       %Power
       Power(c) = (1/2)*ct*p*A*V^3;
       %New Volume Calculation
       NewVolume(c) = VFull - discharge(c);
       VFull=NewVolume(c);
       %New h1
       h1New(c) = ((VFull - discharge(c))/al);
       h1=h1New(c);
    end
end

LagoonOutput.m

function LagoonOutput(Power, h1New)
    %Function 3 
    %Power Plot
    b = Power(:,1:7644);
    z = NewTime;
    plot(z,b)
    xlabel('Time (s)')
    ylabel('Power (W)')
    title('Time vs Power')
    % Height Plot
    h = h1New(1:7644,:);
    y = z;
    plot(y,h)
    xlabel('Time (s)')
    ylabel('Height (m)')
    title('Time vs Height')
end

And here is a main script which calls each function.

mainScript.m

[time, height]=LagoonInput;

[h1,Power]=LagoonProcess(time, height);

LagoonOutput(Power, h1New);

Powertotal= sum(Power);

Instead of saving each function as separate files, you can use nested functions. Below is a documentation link.

https://www.mathworks.com/help/matlab/matlab_prog/nested-functions.html