quantax.state.DenseState

class quantax.state.DenseState

Bases: State

Dense state in which the full wave function is stored as a numpy array

__init__(wave_function: ndarray | Array, symm: Symmetry | None = None)

Parameters:

• wave_function – Full wave function given according to the basis.states order in QuSpin

• symm – The symmetry of the wave function, default to quantax.symmetry.Identity

__getitem__(basis_ints: ndarray | Array) → ndarray

Evaluate the wave function \(\psi(s) = \left<s|\psi\right>\) by state[s]. This is done by slicing the full wave function.

Parameters:

basis_ints – A batch of basis integers

__call__(fock_states: ndarray | Array, **kwargs) → ndarray

Evaluate the wave function \(\psi(s) = \left<s|\psi\right>\) by state(s). This is done by converting fock states basis integers and slicing the full wave function.

Parameters:

fock_states – A batch of fock states with entries \(\pm 1\)

property wave_function: ndarray | Array

Full wave function

todense(symm: Symmetry | None = None) → DenseState

Convert the state to a new DenseState with the given symmetry

Parameters:

symm – The new symmetry. It’s default to self.symm, so self without copy is returned by default.

normalize() → DenseState

Normalize the wave function, and return self.

property Nparticle: int | Tuple[int, int] | List[int] | List[Tuple[int, int]] | None

Number of particle convervation of the state

property basis: spin_basis_general

Quspin basis of the state

norm(ord: int | None = None) → float

Norm of state

Parameters:

ord – Order of the norm, default to 2-norm \(\sqrt{\sum_s |\psi(s)|^2}\)

property nsites: int

Number of sites

property nsymm: int

Number of symmetry group elements

overlap(other: State) → Number

Overlap between two states. Equal to self @ other if the two states are normalized.

property symm: Symmetry

Symmetry of the state