Can I use a symbol as a variable?

HI!

In my code, I have declared:

syms m

I have thes huge expressions that contain m in them as a symbol. Later in the code, I want to use m as a varibale in a loop like this:

m= 1:1:20

Is there any way to do this?

Any help will be appreciated.

Answer 1

[Paul]

Hi Prasenjit,

Yes, you can do that

syms m
f = m^2   % expression that contains m as a symbol

f = 

whos m    % m is sym

  Name      Size            Bytes  Class    Attributes

  m         1x1                 8  sym                

for m = 1:1:20;  % loop with m
    m;  % do something with m
end
whos m  % m is now a double

  Name      Size            Bytes  Class     Attributes

  m         1x1                 8  double              

At this point f is still an expression in terms of m

f

f = 

However, the m that is in f is now not related to the variable m in the Matlab workspace. Are you sure that's what you want?

What is the goal of defining expressions in terms of sym m and then using m as a loop variable? If you show a simple example of what you're trying to do someone might be able to help do it in a different or better way.

[Walter Roberson]

if the idea is that you want the loop variable m to become the value of symbolic m, then see subs()