How do i compare cell array values and replace with string of code letters?

% If i have a cell array like, cellArr = {'UUU'}  {'CUU'}  {'UUC'}  {'UUG'} i
% want to create a string with appropriate code as per below eg 'FLFL'
F = {'UUU','UUC'};
L = {'UUA','UUG','CUU','CUC','CUA','CUG'};

% empty string.
amino_acid_chain = strings(1,numel(cellArr));

for i = 1:numel(cellArr)
    amino_acid_chain(i) = strcmpi(cellArr(i), 'UUU');
    
end

The best i can come up with at the moment is to create an empty string array, then use strcmpi (to ignore case), and find a way to replace true entries with appropriate code. Two problems, 1st, i dont know how to compare {'UUU', 'UUC'} instead of just 'UUU', and 2nd, how do i convert true entries to code (F or L). Alternatively, im sure theres probably a much easier way to achieve this so any other advice would be appreciated.

Answer 1

[Stephen23]

Method one:

>> C = {'UUU','CUU','UUC','UUG'};
>> F = {'UUU','UUC'};
>> L = {'UUA','UUG','CUU','CUC','CUA','CUG'};
>> Xf = ismember(C,F)
Xf =
  1  0  1  0
>> Xl = ismember(C,L)
Xl =
  0  1  0  1

And then use indexing:

>> Y = Xf+2*Xl
Y =
   1   2   1   2
>> Z = 'FL';
>> Z(Y)
ans = FLFL

Or even something like:

>> char('F'*Xf + 'L'*Xl)
ans = FLFL

Use upper on ismember's input arguments to get case-insensitive comparisons.

Method two:

>> [~,X] = ismember(C,[F,L]);
>> V = cumsum(cellfun(@numel,{F,L}));
>> Y = 1+sum(V(:)<X)
Y =
   1   2   1   2

Method three:

>> C = {'UUU','CUU','UUC','UUG'};
>> F = {'UUU','UUC'};
>> L = {'UUA','UUG','CUU','CUC','CUA','CUG'};
>> F(2,:) = {'F'};
>> L(2,:) = {'L'};
>> D = [F,L];
>> [~,X] = ismember(C,D(1,:));
>> [D{2,X}]
ans = FLFL

[Damien Williams]

I probably should have mentioned this, the reason i was trying to use a for loop is because i actually have 22 codes to compare the cell array against. I just put 2 in for simplicity.

[Stephen23]

Methods two and three are trivially adapted to work with an arbitrary number of cell vectors (as long as you have sensibly stored them all in one cell array):

>> C = {'UUU','CUU','UUC','UUG'};
>> D = {{'UUU','UUC'},{'UUA','UUG','CUU','CUC','CUA','CUG'},... add them here ...}; 
>> [~,X] = ismember(C,[D{:}]);
>> V = cumsum(cellfun(@numel,D));
>> Y = 1+sum(V(:)<X)
... etc

[Damien Williams]

Thanks alot for your help.