qugrad.HilbertSpace

class qugrad.HilbertSpace(basis: ndarray[int])

Bases: object

Represents a Hilbert space with a prefered basis indexed by non-negative integers.

Note

The class also can be treated as an iterator and will return basis as the iterator.

—

Attributes

basis	An array of positive integers labeling the Hilbert space basis
dim	The Hilbert space dimension
inverse	An array satisfying the property self.inverse[self.basis[i]]=i

Methods

__init__	Initialises a new HilbertSpace.
basis_vector	Returns a column vector represnetation corresponding to the input basis state label.
get_subspace	Generates a new subspace by filtering the basis state labels.
labels	Generates a string (list of strings) that represent the state(s).

__init__(basis: ndarray[int])

Initialises a new HilbertSpace.

Parameters:

basis (NDArray[Shape[dim], int]) – The labels for the basis vectors.

basis_vector(basis_state_label: int) → ndarray[complex128]

Returns a column vector represnetation corresponding to the input basis state label.

Parameters:

basis_state_label (int) – A positive integer denoting the label of the basis state to generate the basis vector for.

Returns:

The basis vector corresponding to the input basis state label.

Return type:

NDArray[Shape[dim], np.complex128]

get_subspace(filter: ndarray[bool]) → HilbertSpace

Generates a new subspace by filtering the basis state labels.

Parameters:

filter (NDArray[Shape[dim], bool]) – True entries are retained in the new subspace.

Returns:

The filtered subspace.

Return type:

HilbertSpace

labels(states: int | list[int] | None = None) → str | list[str]

Generates a string (list of strings) that represent the state(s).

Parameters:

states (int | list[int], optional) – The state(s) to label. If None then the labels for all states in basis are returned. By default None.

Returns:

The label(s) for the specified states.

Return type:

str | list[str]

property basis: ndarray[int]

An array of positive integers labeling the Hilbert space basis

property dim

The Hilbert space dimension

property inverse: ndarray[int]

An array satisfying the property self.inverse[self.basis[i]]=i