Is there any way to convert variables from list to arrays?

I have 2 arrays

a = [1 2 3]
b = [2 3 4]

and a list

c = {'a', 'b'}

when I use cell2mat(c(1,1)), I get a, but what I want is [1 2 3]. Is there any way to achieve it?

[Stephen23]

"I have ... a list"

MATLAB does not have a "list" data type. What you show is called a cell array:

https://www.mathworks.com/help/matlab/cell-arrays.html

https://www.mathworks.com/help/matlab/data-types_data-types.html

Answer 1

[Stephen23]

Simply store the data in one structure, and then it is trivially easy (no slow, buggy eval is required):

>> S.a = [1,2,3];
>> S.b = [2,3,4];
>> C = {'a','b'};
>> S.(C{1})
ans =
   1   2   3

Simpler code through better code design: faster, neater, simpler, more efficient, easiest to debug, less complex. Why waste your time learning bad ways to write code?:

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

Answer 2

[Fangjun Jiang]

a=1:3;
b=2:4;
c={'a','b'};

you could do

d=eval(c{1})

or, you should do

clear c;
c.a=a;
c.b=b;
MyVar='a';
c.(MyVar)

[Stephen23]

Do NOT use eval for trivial code like this. The MATLAB documentation specifically recommends against doing what this answer shows: "A frequent use of the eval function is to create sets of variables such as A1, A2, ..., An, but this approach does not use the array processing power of MATLAB and is not recommended. The preferred method is to store related data in a single array."

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

Using eval is how beginners force themselves into writing slow, complex, buggy code that is hard to debug. Read more here:

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

See my answer for a simple solution that avoids these problems entirely.