delete cell and replace with remaining cells in matlab

for x=1:length(semifinalcode)

newtrim="("+trim_Ainstruction+")";

if semifinalcode{x}==newtrim

semifinalcode{x}={};

out=x;

semifinalcode=semifinalcode(~cellfun('isempty',semifinalcode));

end

end

I want to delete purticular cell after if loop and replace with remaining data in that array, but failed. tried in the above way. can anyone help? where 'semifinal ' datatype is cell type array.

Answer 1

[Voss]

If you delete elements from an array (of any type including a cell array) from within a for loop that loops over the elements of that same array, you're going to run into the situation where your loop index exceeds the size of the array, because the array decreases in size as the loop goes along, but the indexes to use are set when the loop starts. For example, if I make a vector [1 2 3 4 5], then use a for loop to remove any 3's, I'll get an error when I try to check the 5th element because by that time the array only has 4 elements:

try
    A = [1 2 3 4 5];
    for i = 1:numel(A)
        if A(i) == 3
            A(i) = [];
        end
    end
catch ME
    display(ME.message);
end

Index exceeds the number of array elements. Index must not exceed 4.

Instead, you can mark the elements for deletion during the loop, but then delete them all only once the loop has completed:

A = [1 2 3 4 5];
to_be_deleted = false(size(A));
for i = 1:numel(A)
    if A(i) == 3
        to_be_deleted(i) = true;
    end
end
A(to_be_deleted) = [];
display(A);

A = 1×4

1 2 4 5

So in your case you might try something like this:

semifinalcode = {"(ok)" "(baba)" "(booey)"};
trim_Ainstruction = "baba";

to_be_deleted = false(size(semifinalcode));
for x = 1:numel(semifinalcode)
    newtrim = "(" + trim_Ainstruction + ")";
    if semifinalcode{x} == newtrim
        to_be_deleted(x) = true;
    end
end
% out = find(to_be_deleted); % how it should be?
out = find(to_be_deleted,1,'last'); % how it was
semifinalcode(to_be_deleted) = [];

display(semifinalcode);

semifinalcode = 1×2 cell array
    {["(ok)"]}    {["(booey)"]}

[Voss]

@VISHNU DIVAKARAN PILLAI: Did this answer work for you?