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

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.

Answer 1

[Ameer Hamza]

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]

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.

instead of

B= (1x9 cell) and inside the cell each of the 9 elements is 1x6

[VBBV]

A = {A1, A2, A3, .., AN};
for i = 1:numel(A)
  B{i} = A{i}*2; 
end
B

Use the for loop index i.