dq.unit

unit(x: QArrayLike, *, psd: bool = True) -> QArray

Normalize a ket, bra, density matrix or Hermitian matrix to unit norm.

The returned object is divided by its norm (see dq.norm()).

Parameters

• x (qarray-like of shape (..., n, 1) or (..., 1, n) or (..., n, n)) –

  Ket, bra or density matrix.

• psd –

  Whether x is a positive semi-definite matrix (see dq.norm()).

Returns

(qarray of shape (..., n, 1) or (..., 1, n) or (..., n, n)) Normalized ket, bra or density matrix.

See also

• dq.norm(): returns the norm of a ket, bra, density matrix, or Hermitian matrix.

Examples

>>> psi = dq.fock(4, 0) + dq.fock(4, 1)
>>> psi.norm()
Array(1.414, dtype=float32)
>>> psi = dq.unit(psi)
>>> psi.norm()
Array(1., dtype=float32)