How to assign a name to a Table given set of names?

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Hi folks. I have a long code which runs every time with the number of items a set. For instance I have a set: Subjects = {Name1,Name2,Name3}. My FOR produces 3 different tables/matrixes: A, B and C. So each time the FOR statement runs, it overwrites the tables generated for each different subject. Is there a way to insert a code inside my FOR statement to store each table/matrix (A,B,C) and name each after the subject? For instance, something like this:
Subjects = {'Name1','Name2','Name3'}
for i=1:length(Subjects)
A = magic(2)
B = magic(3)
C = magic(4)
strcat('A_',Subjects(1)) = A % These were my best attempts, But It doesn't work.
strcat('B_',Subjects(2)) = B
strcat('C_',Subjects(3)) = C
end
% Any help much appreciated.
  2 Comments
Adam
Adam on 6 Apr 2016
I assume you mean matrices rather than tables. A table is now a specific data type in Matlab so it is useful to be as specific as you can with terminology. Your code suggests these are simply matrices though.
Stephen23
Stephen23 on 6 Apr 2016
Edited: Stephen23 on 6 Apr 2016
Use Adam's answer, it is the best solution to your problem.
Creating variables dynamically is a really bad way to code, which is explained in lots of threads on this forum:

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Accepted Answer

Ralf
Ralf on 6 Apr 2016
Edited: Ralf on 6 Apr 2016
Hi Edson,
would that work for you?
assignin('base', ['A_' Subjects{1}], A);
  3 Comments
Guillaume
Guillaume on 6 Apr 2016
Edited: Guillaume on 6 Apr 2016
As a rule, do not use assignin, evalin, eval and similar. Do not create variable names dynamically and do not embed metadata in variable names. The metadata belongs in the content of the variable not its name.
Creating variable names dynamically is slow, is a nightmare to debug, makes subsequent code a lot more complicated, and may also not always work.
Adam's answer is a much better way of doing what you want.
Ralf
Ralf on 6 Apr 2016
Guillaume, you are absolutely right. Assignin and evalin are "quick and dirty" solutions. I must admit that Adam's solution is much better.

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More Answers (1)

Adam
Adam on 6 Apr 2016
Edited: Adam on 6 Apr 2016
Taking your current solution and making minimal changes, rather than starting from scratch...
Subjects = {'Name1','Name2','Name3'}
for i=1:numel(Subjects)
A.( Subjects{i} ) = magic(2)
B.( Subjects{i} ) = magic(3)
C.( Subjects{i} ) = magic(4)
end
will give you structs A, B and C with a field for each subject containing the relevant matrix.
You can then get hold of these fields using dynamic strings in the same way I do above.
  1 Comment
Edson
Edson on 6 Apr 2016
Thanks very much Adam for your answer. I think I can work with Ralf's and yours on my code. Have a great day!

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