How to substitute multiple symbols in an expression in sympy?

Question

Assigning a variable directly does not modify expressions that used the variable retroactively.

>>> from sympy import Symbol
>>> x = Symbol         


        

Answer 1

Actually sympy is designed not to substitute values until you really want to substitute them with subs (see http://docs.sympy.org/latest/tutorial/basic_operations.html)

Try

f.subs({x:0})
f.subs(x, 0) # as alternative

instead of

x = 0