Creating variables in a foor loop using num2str

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Hi,
title probably says it all. I want to create variables according to the i in the loop. I just don't even know if I can incorporate the function (I've already tried num2str, eval, evalc, sprintf) into variable definition. Below is a non-working code just to illustrate what I mean to do (hopefully). This example is just for 3 different variables but later on, I need to do this for about 60 more variables. I just cannot quite put my hand on the right formulation of the loop.
Thank you for any advices
%%% years_10 = [xvalues, yvalues]... n*2 matrices
years_10=readmatrix('10_years.csv');
years_20=readmatrix('20_years.csv');
years_30=readmatrix('30_years.csv');
for i=10:10:30
years_num2str(i) = readmatrix(sprintf('%d_years.csv',i);
end
  2 Comments
Walter Roberson
Walter Roberson on 23 Nov 2022
Why do you think this is necessary? Why not use a cell array instead?
Stephen23
Stephen23 on 8 Dec 2022
Edited: Stephen23 on 8 Dec 2022
The easy, simple, and very efficient approach is to use indexing into one array, e.g. a cell array or structure array.
Using indexing is shown in the MATLAB documentation:

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Accepted Answer

William Rose
William Rose on 23 Nov 2022
Edited: William Rose on 23 Nov 2022
[edit: change "v" to "s" in my description, to match the code]
N=50;
for i=10:10:N, s.(strcat('a',num2str(i)))=i^2; end
disp(s)
a10: 100 a20: 400 a30: 900 a40: 1600 a50: 2500
creates a structure s with fields a10, a20, ..., a50. Each one equals a scalar. You could initialize each one to be a vector or array, if you prefer.
  5 Comments
Mady
Mady on 7 Dec 2022
Thank you @William Rose for quite a handy solution. The tutorial about Dynamic variable naming is very useful, lots of new informations :)

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