sympy

[Gregory Ewing]

Steven D'Aprano wrote:
> On Thu, 31 Mar 2016 02:23 am, Poul Riis wrote:
> 
>>What I intend to do is to let sympy find the derivative of some
>>welldefined function and next define the foundation derivative as a normal
>>function
> 
> py> ftext.evalf(subs={x:3})
> -0.0600000000000000

Given all that, it looks like you want

def f(t):
   return ftext.evalf(subs={x:t})

-- 
Greg