dq.spost
spost(x: QArrayLike) -> QArray
Returns the superoperator formed from post-multiplication by an operator.
Post-multiplication by matrix \(A\) is defined by the superoperator \(A^\mathrm{T} \otimes I_n\) in vectorized form: $$ XA \to (A^\mathrm{T} \otimes I_n) \kett{X}. $$
Parameters
-
x
(qarray-like of shape (..., n, n))
–
Operator.
Returns
(qarray of shape (..., n^2, n^2)) Post-multiplication superoperator.
Examples
>>> dq.spost(dq.destroy(3)).shape
(9, 9)