# central_charge_from_S_profile¶

tenpy.tools.fit.central_charge_from_S_profile(psi, exclude=None)[source]

Fit the entanglement entropy of a finite MPS to the expected profile for critical models.

See entropy_profile_from_CFT() for the function we fit to.

Parameters
• psi (MPS) – Ground state of a finite system at a critical point (i.e. gapless!). The bond dimension should be large enough to be converged!

• exclude (int) – How many sites at the left (and at the right) boundary to exclude from the fit (to avoid boundary effects). Defaults to psi.L // 4

Returns