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cfunctions

cf_wigner(psi, xvec, yvec)

Wigner function for a state vector or density matrix at points xvec + i * yvec.

Parameters

Qarray

A state vector or density matrix.

array_like

x-coordinates at which to calculate the Wigner function.

array_like

y-coordinates at which to calculate the Wigner function.

Returns

array

Values representing the Wigner function calculated over the specified range [xvec,yvec].

Source code in jaxquantum/core/cfunctions.py 
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def cf_wigner(psi, xvec, yvec):
    """Wigner function for a state vector or density matrix at points
    `xvec + i * yvec`.

    Parameters
    ----------

    state : Qarray
        A state vector or density matrix.

    xvec : array_like
        x-coordinates at which to calculate the Wigner function.

    yvec : array_like
        y-coordinates at which to calculate the Wigner function.


    Returns
    -------

    W : array
        Values representing the Wigner function calculated over the specified
        range [xvec,yvec].


    """
    N = psi.dims[0][0]
    x, y = jnp.meshgrid(xvec, yvec)
    alpha = x + 1.0j * y
    displacement = jqt.displace(N, alpha)

    vmapped_overlap = [vmap(vmap(jqt.overlap, in_axes=(None, 0)), in_axes=(
        None, 0))]
    for _ in psi.bdims:
        vmapped_overlap.append(vmap(vmapped_overlap[-1], in_axes=(0, None)))

    cf = vmapped_overlap[-1](psi, displacement)
    return cf