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dq.wigner 

wigner(
    state: ArrayLike,
    xmax: float = 6.0,
    ymax: float = 6.0,
    npixels: int = 201,
    xvec: ArrayLike | None = None,
    yvec: ArrayLike | None = None,
    g: float = 2.0,
) -> tuple[Array, Array, Array]

Compute the Wigner distribution of a ket or density matrix.

The Wigner distribution is computed on a grid of coordinates \((x, y)\).

Parameters

  • state (array_like of shape (..., n, 1) or (..., n, n)) –

    Ket or density matrix.

  • xmax –

    Maximum absolute value of the \(x\) coordinate.

  • ymax –

    Maximum absolute value of the \(y\) coordinate.

  • npixels –

    Number of pixels in each direction.

  • xvec (array_like of shape (nxvec,), optional) –

    \(x\) coordinates. If None, defaults to xvec = jnp.linspace(-xmax, xmax, npixels).

  • yvec (array_like of shape (nyvec,), optional) –

    \(y\) coordinates. If None, defaults to yvec = jnp.linspace(-ymax, ymax, npixels).

  • g –

    Scaling factor of Wigner quadratures, such that \(a = g(x + iy)/2\).

Returns

A tuple (xvec, yvec, w) where

  • xvec (array of shape (npixels,) or (nxvec,)) -- \(x\) coordinates, or xvec if specified.
  • yvec (array of shape (npixels,) or (nyvec,)) -- \(y\) coordinates, or yvec if specified.
  • w (array of shape (..., npixels, npixels) or (..., nyvec, nxvec)) -- Wigner distribution.