how to sample time of input vector in matlabb script

Dear all, Ihave an optimization algorithm function (MPPT) the algorithm function receive input vector, i want to sample the time between inputs like i do in simulink by insurting zero order hold block(attached in photo) but in code how to do it ? what is its effect on the overal system in terms of efficiency, speed and especially stability?

[Mathieu NOE]

hello

most of your simulink file works with discrete signals (after the ZOH)

if you define signals as arrays in matlab with appropriate sample rate and lenght , it's like working on sampled signals in Simulink

as soon as your matlab script does the same job as your simulink file , there should be no differences at the end

[YASSER]

in simulink i can slow the process of input by changing sample time i want to know how to do it in matlab in order to introduce an inner loop that has big responce time

[Mathieu NOE]

in matlab you can also play with sample times , you can reduce it with decimate , resample , interp1

Answer 1

[Jaimin]

Hi @YASSER

To implement a Zero-Order Hold (ZOH) programmatically, you can hold input values constant for a specified sample period, similar to using a ZOH block in MATLAB's Simulink.

Kindly refer following code for better understanding:

function zero_order_hold_example()
    holdTime = 1.0; % Hold time in seconds
    totalDuration = 5.0; % Total duration in seconds
   
    inputVector = [1, 2, 3];
    
    numIterations = floor(totalDuration / holdTime);
   
    for i = 1:numIterations
        % Hold the input vector
        currentInput = inputVector;
        disp(['Current Input at iteration ', num2str(i), ': ', mat2str(currentInput)]);
        
        % Pause for the hold time
        pause(holdTime);
    end
end

Using a ZOH in MATLAB can enhance computational efficiency by reducing input processing frequency, but it may decrease system responsiveness and impact stability due to potential delays, necessitating careful tuning and analysis.

For more information kindly refer following MathWorks documentation.

https://www.mathworks.com/help/matlab/ref/pause.html

I hope this will helpful.