Create n symbolic variables

Hi, I would like to know if there's a way to create n differente symbolic variables (n is an input). Thank's in advanced

Answer 1

[madhan ravi]

EDITED

n=input('value of n?')

syms(sym('a',[1 n]))

a=(sym('a',[1 n])) %storing symbolic variables in a vector for convenience and also to use indexing

command window displays:

value of n?10

n =

      10

a =

[ a1, a2, a3, a4, a5, a6, a7, a8, a9, a10]

>> a(1:6)

ans =

[ a1, a2, a3, a4, a5, a6]

>>

The above is strictly not recommended though please see http://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

[madhan ravi]

The above shows an example of creating n symbolic variables

[madhan ravi]

If it’s what you want accept the answer so other people know the question is solved else let know

[Walter Roberson]

Note that this creates a single variable, A, that contains a vector of symbolic expressions that refer to symbolic variables that live in the symbolic engine, same as if you had done

A = [sym('A1'), sym('A2'), sym('A3'), ... sym('A20')];

The code does not create variables A1, A2, A3, ... A20 at the MATLAB level. You will not see them in the workspace; you will only see A in the workspace.

If you need to create them at the MATLAB level, then chances are that you should be coding differently.

[madhan ravi]

Yes sir I thought the OP asked to simply create variable to be used further in mathematical equations

[madhan ravi]

Edited the answer sir Walter, thank you for pointing it out

[Walter Roberson]

syms(sym('a',[1 n]))

That does work to create the variables in the MATLAB workspace, but any time you are creating a variable number of variables in the MATLAB workspace you should stop yourself and ask if it is strictly necessary to do so, as there is almost always a better way.

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

[madhan ravi]

Oh yes sir Walter didn’t think of it actually thank you once again

[one plus one is two]

Sorry for the late, thank you so much for your help!

[madhan ravi]

Anytime :)