Can MATLAB recognized the name of a variable with input function?

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I haven't tried yet, but what I want to do is ask the user for an input. For example,
x = input('what is the name of the object?')
The user will only be able to input a certain name of objects. Let's say the user chose milk and in the code milk is as follows:
milk = 30;
Can MATLAB display 30?
Thank you in advance
  1 Kommentar
Stephen23
Stephen23 am 15 Sep. 2021
Bearbeitet: Stephen23 am 15 Sep. 2021
"Can MATLAB display 30?"
Yes, but your approach forces you into writing slow, complex, inefficient, obfuscated code which is difficult to debug. Here are two much better approaches, first is to use the fields of a structure (or you can do much the same with a table):
S.beer = [1,2,3];
S.milk = [4,5,6];
x = 'milk'; % user input
S.(x)
ans = 1×3
4 5 6
Second is to simply and very efficiently store the names as data in their own right (which of course as meta-data they are) and then use basic MATLAB indexing:
M = [1,2,3;4,5,6];
C = ["beer","milk"];
M(strcmpi(x,C),:)
ans = 1×3
4 5 6
Understanding that meta-data is data is an important step to writing better code.
Avoiding INPUT means that you can write testable, expandable, callable code.

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Chunru
Chunru am 15 Sep. 2021
It's possible but it should be avoided if possible.
milk = 30;
%x = input('what is the name of the object? ', 's') % use this in your program
x = 'milk'; % for the on-line version
if exist(x, 'var')
eval(x);
else
fprintf('The variable %s does not exist\n', x);
end
milk = 30
  2 Kommentare
Ana D Chavez Gonzalez
Ana D Chavez Gonzalez am 15 Sep. 2021
Why should it be avoided? if I may know
DGM
DGM am 15 Sep. 2021
Bearbeitet: DGM am 15 Sep. 2021
This is a brief explanation
This post explains issues with using eval(), and puts it in context with related topics regarding common usage patterns.

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