# how to work with variables with different names in a loop?

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Lucrezia Cester on 13 Feb 2021
Commented: Lucrezia Cester on 13 Feb 2021
Hello,
I have a bunch of data taken in the lab which has names such as A1,A2... AN ... ETC.
How can I work with these data sets in a loop such as
for a=1:N
B=A{N} *2
end
where N changes at each iteration and inserts the next data set saved with a different name.
Thanks, Cheers.

Ameer Hamza on 13 Feb 2021
It is never a good idea to create a variable name like this: A1, A2, ..., AN. Read here: https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval. There is no good way to access values of these variables in a loop. It is better to create an array which is easier to loop over. For example, create a cell array
A = {A1, A2, A3, .., AN};
for i = 1:numel(A)
B = A{i}*2
end
Lucrezia Cester on 13 Feb 2021
Hello, thank you very much for your answer. Can I also ask you, after performing this operation, it only saves the last output.
i=9
for i = 1:numel(A)
B = mat2cell( A{i},[1],[3666 3666 3666 3666 3666 3666])
end
like so
B= 1x6 cell
which is the last iteration where i=9.
B= (1x9 cell) and inside the cell each of the 9 elements is 1x6