entanglish.PureStEnt module

class entanglish.PureStEnt.PureStEnt(den_mat, approx='eigen', num_bstrap_steps=1, check_purity=True, verbose=False)

Bases: entanglish.EntangCase.EntangCase

This class is a child of class EntangCase. Its purpose is to calculate the ( bipartite) quantum entanglement E_xy of a pure state |psi_xy> where x and y constitute a bi-partition of the set of all qudits. E_xy is defined here as the von Neumann entropy S(dm_x) of a density matrix dm_x, where dm_x = trace_y dm_xy, where dm_xy = |psi_xy><psi_xy|.

Variables:den_mat (DenMat) –

__init__(den_mat, approx='eigen', num_bstrap_steps=1, check_purity=True, verbose=False)

Constructor. If check_purity = True, checks that den_mat is a pure state (has rank 1)

Parameters:

• den_mat (DenMat) –
• approx (str) –
• num_bstrap_steps (int) –
• check_purity (bool) –
• verbose (bool) –

get_entang(axes_subset)

This method returns the von Neumann entropy S(dm_x), where dm_x = trace_y dm_xy, where x = axes_subset, and y is the set of all other axes.

Parameters:axes_subset (set[int]) – Returns: Return type:float