How can i create variables from a string?

Question

Le Dung 2017-5-18

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https://ww2.mathworks.cn/matlabcentral/answers/340777-how-can-i-create-variables-from-a-string

编辑： Stephen23 2019-10-7

Hi! I want to create an array of variables m1,m2,m3,....,mn, that are created by join "m" with array "1,2,3,...,n" I wrote a code (below), and i want to after run it, Matlab returns: m1=1 m2=5

M=[1 2 3;
    4 5 6;
    7 8 9];
mch=diag(M,0)';
x=2;
for i=1:x
    ha=num2str(i);
    m(ha)= mch(i);
end

Thank you so much!

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Stephen23 2017-5-18

编辑：Stephen23 2019-6-25

@Le Dung: this will make your code slow, buggy, hard to debug, hard to read, and obfuscated.

https://www.mathworks.com/help/matlab/matlab_prog/string-evaluation.html

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

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Answer 1

KSSV 2017-5-18

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https://ww2.mathworks.cn/matlabcentral/answers/340777-how-can-i-create-variables-from-a-string#answer_267448

在 MATLAB Online 中打开

Why you need a dynamic variable naming? This is not suggested and you should avoid.

https://in.mathworks.com/matlabcentral/answers/105936-how-to-make-dynamic-variable-names-a1-a2-an-with-for-loop-using-eval-num2str

You have matrix already and you can happily call them:

M=[1 2 3;
    4 5 6;
    7 8 9];
M(1)    % is M1
M(2)    % is M2
M(6)    % is M6
.
.
.M(i)   % is Mi where  i <= numel(M)

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Stephen23 2017-5-18

编辑：Stephen23 2019-10-7

在 MATLAB Online 中打开

"But, because i want to make a general problem"

Yes, you are trying to make a general problem. And KSSV gave you a general solution instead.

Good work, KSSV.

M = [1,2,3;4,5,6;7,8,9];
mch = diag(M,0); % this is all you need

Sami Aldalahmeh 2019-10-7

I believe that you should answer the question if you can not discourage the user. Giving advice in a polite way, on the other hand, is always welcomed.

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