DifferentiableUnitary.get_grad
- abstract DifferentiableUnitary.get_grad(params=[])[source]
Return the gradient for the unitary map as an np.ndarray.
- Parameters:
params (
RealVector
) – The unitary parameters, seeUnitary.get_unitary()
for more info.- Returns:
The (num_params,N,N)-shaped, matrix-by-vector derivative of this unitary at the point specified by params.
- Return type:
np.ndarray
Notes
The gradient of a unitary is defined as a matrix-by-vector derivative. If the UnitaryMatrix result of get_unitary has dimension NxN, then the shape of get_grad’s return value should equal (num_params,N,N), where the return value’s i-th element is the matrix derivative of the unitary with respect to the i-th parameter.