qiskit.quantum_info.mutual_information¶
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mutual_information(state, base=2)[source]¶ Calculate the mutual information of a bipartite state.
The mutual information \(I\) is given by:
\[I(\rho_{AB}) = S(\rho_A) + S(\rho_B) - S(\rho_{AB})\]where \(\rho_A=Tr_B[\rho_{AB}], \rho_B=Tr_A[\rho_{AB}]\), are the reduced density matrices of the bipartite state \(\rho_{AB}\).
- Parameters
state (Statevector or DensityMatrix) – a bipartite state.
base (int) – the base of the logarithm [Default: 2].
- Returns
The mutual information \(I(\rho_{AB})\).
- Return type
float
- Raises
QiskitError – if the input state is not a valid QuantumState.
QiskitError – if input is not a bipartite QuantumState.