Calculate the error from the project_onto_sector function.

operator the QubitOperator to work on
qubits a list of indices of qubits in operator to remove
sectors for each qubit, whether to project into the 0 subspace (=1) or the 1 subspace (=-1).

error the trace norm of the removed term.

TypeError operator must be a QubitOperator.
TypeError qubits and sector must be an array-like.
ValueError If qubits and sectors have different length.
ValueError If sector are not specified as 0 or 1.