How to compute numeric approximation of symbolic expression?

I have a derivative of a function, and Octave displays it as an expression:

  10____ ⎛  10          ⎞
  ╲╱ 11 ⋅⎜- ── + log(11)⎟
         ⎝  11          ⎠

This is nice and tidy, and completely accurate. However, I would like to get a numerical approximation of said expression, without manually typing the expression (which seems counter-intuitive to me). I can't figure out how to do this, but I probably just don't know what exactly to search for (English is not my native language), and therefore I can't tell if this question is a duplicate.

This is how I got there:

octave> f(x)=(1+(1/x))^x
f(x) = (symfun)

         x
  ⎛    1⎞ 
  ⎜1 + ─⎟ 
  ⎝    x⎠ 

octave> F(x)=diff(f(x))
F(x) = (symfun)

         x                         
  ⎛    1⎞  ⎛   ⎛    1⎞       1    ⎞
  ⎜1 + ─⎟ ⋅⎜log⎜1 + ─⎟ - ─────────⎟
  ⎝    x⎠  ⎜   ⎝    x⎠     ⎛    1⎞⎟
           ⎜             x⋅⎜1 + ─⎟⎟
           ⎝               ⎝    x⎠⎠

octave> F(0.1)
warning: passing floating-point values to sym is dangerous, see "help sym"
[...]

  10____ ⎛  10          ⎞
  ╲╱ 11 ⋅⎜- ── + log(11)⎟
         ⎝  11          ⎠

Solution

I think you need the eval function

https://octave.org/doc/v4.0.1/Evaluation.html

For instance

>> eval("log(11)")
ans =  2.3979