String to variable name MATLAB

Question

If for instance I have a variable xa=2, and then I construct a string by joining 'x' and 'a', how can I make this new string have the value 2?

xa=2;
var=strcat('x','a');

The result of this is var=xa, but what I want is var=2.

Thank you

Use eval() : mathworks.com/help/matlab/ref/eval.html EDIT: Code tested, posted an answer. — Yellows
– Yellows, Commented Feb 11, 2015 at 13:52
You can do this, but you shouldn't do it... A map/dictionary would be a better approach, even though also not very idiomatic in MATLAB. — knedlsepp
– knedlsepp, Commented Feb 11, 2015 at 14:02
There are at least 5 different reasons why eval should not be used. — rayryeng
– rayryeng, Commented Feb 11, 2015 at 22:54
The reason why I wanted to do it is because the script prompts the user for a project folder, which can be for instance 'C1'. After that the script will go into that folder and load 'positiveInstancesC1.mat', and the variable 'positiveInstancesC1' will be used several times afterwards. So concatenating strings was what I could think about to be able to make the script work only with the input of the folder name, and not changing the variable in the script. But probably there is a better way to do it I am unaware about. — Zynk
– Zynk, Commented Feb 12, 2015 at 9:14

Yellows · Accepted Answer · 2015-02-11 13:56:06Z

4

Use eval():

var = eval(strcat('x','a'));

It will "evaluate" the string 'xa' and translate it to the value of the variable xa.

answered Feb 11, 2015 at 13:56

Yellows

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