Why this Matlab Funcation does not run and every time show such type of error

function duty = algorithm(vpv,ipv,delta)
% I used the MPPT algorithm in the MATLAB examples
% I only modify somethings.
duty_init = 0.1;
% min and max value are used to limit duty between 
% 0 and 0.85
duty_min=0;
duty_max=0.85;

persistent Vold Pold duty_old;
% persistent variable type can be store the data 
% we need the old data by obtain difference 
% between old and new value 
if isempty(Vold)
    Vold=0;
    Pold=0;
    duty_old=duty_init;
end 
P= vpv*ipv; % power 
dV= vpv - Vold;   % differnce between old and new voltage
dP= P - Pold;   % Differnce between old and new power 

% the algorithm in below search the dP/dV=0
% if the derivative equal to zero
% duty will not change 
% if old and new power not equal 
% &
% pv voltage bigger then 30v
% the algorithm will works 
if dP ~= 0 && vpv>30
    if dP < 0
        if dV < 0 
            duty = duty_old - delta;
        else
            duty = duty_old + delta;
        end 
    else 
        if dV <0 
            duty = duty_old + delta;
        else 
            duty = duty_old - delta;
        end
    end 
end 
       duty = duty_old;
end

% the below if limits the duty between min and max 
if duty >= duty_max
    duty=duty_max;
elseif dutycycle_min
    duty=duty_min;
end
%stored data
duty_old=duty;
vold=vpv;
Pold = p;

Answer 1

[Cris LaPierre]

Because the last 10 lines of your code are outside the end that terminates the function. Fix that error, and then see what errors remain. Is this what you intended?

function duty = algorithm(vpv,ipv,delta)
% I used the MPPT algorithm in the MATLAB examples
% I only modify somethings.
duty_init = 0.1;
% min and max value are used to limit duty between 
% 0 and 0.85
duty_min=0;
duty_max=0.85;

persistent Vold Pold duty_old;
% persistent variable type can be store the data 
% we need the old data by obtain difference 
% between old and new value 
if isempty(Vold)
    Vold=0;
    Pold=0;
    duty_old=duty_init;
end 
P= vpv*ipv; % power 
dV= vpv - Vold;   % differnce between old and new voltage
dP= P - Pold;   % Differnce between old and new power 

% the algorithm in below search the dP/dV=0
% if the derivative equal to zero
% duty will not change 
% if old and new power not equal 
% &
% pv voltage bigger then 30v
% the algorithm will works 
if dP ~= 0 && vpv>30
    if dP < 0
        if dV < 0 
            duty = duty_old - delta;
        else
            duty = duty_old + delta;
        end 
    else 
        if dV <0 
            duty = duty_old + delta;
        else 
            duty = duty_old - delta;
        end
    end 
end 
duty = duty_old;


% the below if limits the duty between min and max 
if duty >= duty_max
    duty=duty_max;
elseif dutycycle_min
    duty=duty_min;
end
%stored data
duty_old=duty;
vold=vpv;
Pold = p;

end

[Vinod Suthar]

Sir i don't have how to remove it so please you send me updated code please

[Cris LaPierre]

I did

[Vinod Suthar]

Thank you so much sir send me updated code...

[Cris LaPierre]

I did. See the code in my earlier reply.

[Vinod Suthar]

sir they are show such problem

[Cris LaPierre]

Go through the errors one by one and address them each individually. For example, in the first message, you are told that you need to change your current directory. In errors 2 and 3, you need to adjust your sample time.