Repeating or rerunning a loop

Hello MATLAB community! I am hopeful that someone can help me solve this puzzle I've created for myself...

I am running an experiment using an eye tracker. When an eye movement is detected, I want to record the trial sequence number and then add those trials onto the end of the trial block. But once I'm through the loop I don't know how to restart the loop with a new sequence/new number of iterations.

This is an example of my loop (the real loop is quite long and complex)

seq = [3, 1, 2, 1, 3, 2]; % trial sequence
nTrials = length(seq);
addTrials = []; 

for trial = 1:nTrials
    
    option = seq(trial);
    
    if option == 1
        % do this
    elseif option == 2
        % do that
    elseif option == 3
        % do another thing
    end
    
    movement = 0; 
    % check for eye movements
    if eye movement is detected % this is not real code
        movement = movement + 1
    end
    
    % add trial with movement to new sequence vector
    if movement > 0
        addTrials = [addTrials option];
    end 
end

% Question: how can I get the loop to rerun using 
% nTrials = length(addTrials) and option = addTrials(trial)

I am also open to other ways to solve this than I've currently started!

Thanks!

[Jos (10584)]

In this pseudo-code you can omit the whole movement variable. Did you take a look at my answer?

[Olivia Krieger]

Hi, I check for eye movements in various places within the trial loop, so I've just added (from your suggestion)

if movement > 0
    seq(end + 1) = option;
end

Thank you!!

Answer 1

[Jos (10584)]

Use a while loop, which is more flexible than a for -loop. Something like this might work:

seq = [3, 1, 2, 1, 3, 2]; % trial sequence
k = 0 ; 
while k < length(seq),
    k  = k + 1 ;
    option = seq(k);

    % check for eye movements
    if eye movement is detected % this is not real code
        % add trial with movement to the sequence vector
        seq(end+1) = option ;
    end
end

[Olivia Krieger]

Thank you!! This is very helpful and should work to resolve my issue, it worked in a little psuedocode I made. I will implement today in the actual experiment!