|View source on GitHub|
Returns a DepolarizingChannel with given probability of error.
cirq.depolarize( p: float, n_qubits: int = 1 ) ->
Used in the notebooks
|Used in the tutorials|
This channel applies one of \(4^n\) disjoint possibilities: nothing (the identity channel) or one of the \(4^n - 1\) pauli gates. The disjoint probabilities of the non-identity Pauli gates are all the same, \(p / (4^n - 1)\), and the identity is done with probability 1 - p. The supplied probability must be a valid probability or else this constructor will raise a ValueError.
This channel evolves a density matrix via
\[ \rho \rightarrow (1 - p) \rho + p / (4^n - 1) \sum _i P_i \rho P_i \]
where \(P_i\) are the \(4^n - 1\) Pauli gates (excluding the identity).
||The probability that one of the Pauli gates is applied. Each of the Pauli gates is applied independently with probability \(p / (4^n - 1)\).|
||The number of qubits.|
||if p is not a valid probability.|