有没有办法在 sympy 中递归和自动替换？

Question

I am coming from Mathematica, where you can do the following to fully substitute:

In[1]:=

x=y
y=z
Simplify[x]

Out[1]=

z

Is there a way of doing this automatically in SymPy? I am aware that I can manually substitute the variables 1 by 1 using subs or solve , or by doing something janky like this:

In[1]:

y=z
x=y
x

Out[1]:

z

but is there a way of making it automatically get the most expanded and substituted expression solving for 1 variable?

Answer 1

There is a proof of concept code here that handles multiple equations.

from sympy.abc import x, y, z
eqs = [Eq(x,y),Eq(y,z)]
focus(eqs, z)  # function defined in link
{z: x}