calculate inductance z11

How can I calculate inductance through s2p file ?
As what I know about that , L=Z11/(2*pi*freq)
Z11 can be calculated through s2p.
But why is the manual calculation and simulation different ?

tks

Hi, myem:

I don't think your formula is correct.

You should replace Z11 with 1/Y11. Z11 is not the same as 1/Y11.

Regards,

I always use the equation of L=im(Zin)/(2*pi*freq)
to get inductance.
Is Z11 is equal to Zin ?

TKS

Added after 1 hours 20 minutes:

I always use the equation of L=im(Zin)/(2*pi*freq)
to get inductance.
Is Z11 is equal to Zin ?

TKS

For 1-port, it is ok because Z11 = 1 / Y11. For 2-ports, it is not correct because Z11 is not the same as 1/Y11. You mentioned s2p and I assume you are talking about 2-ports.