# X¶

Module: pennylane

class X(wires)[source]

The position quadrature observable $$\hat{x}$$.

When used with the expval() function, the position expectation value $$\braket{\hat{n}}$$ is returned. This corresponds to the mean displacement in the phase space along the $$x$$ axis.

Details:

• Number of wires: 1

• Number of parameters: 0

• Observable order: 1st order in the quadrature operators

• Heisenberg representation:

$d = [0, 1, 0]$
Parameters: wires (Sequence[int] or int) – the wire the operation acts on