qiskit.circuit.library.Isometry(isometry, num_ancillas_zero, num_ancillas_dirty, epsilon=1e-10)
Decomposition of arbitrary isometries from to qubits.
In particular, this allows to decompose unitaries (m=n) and to do state preparation ().
The decomposition is based on .
 Iten et al., Quantum circuits for isometries (2016).
- isometry (np.ndarray) – An isometry from to :math`n` qubits, i.e., a complex
np.ndarrayof dimension with orthonormal columns (given in the computational basis specified by the order of the ancillas and the input qubits, where the ancillas are considered to be more significant than the input qubits).
- num_ancillas_zero (int (opens in a new tab)) – Number of additional ancillas that start in the state (the ancillas required for providing the output of the isometry are not accounted for here).
- num_ancillas_dirty (int (opens in a new tab)) – Number of additional ancillas that start in an arbitrary state.
- epsilon (float (opens in a new tab)) – Error tolerance of calculations.
Get the base class of this instruction. This is guaranteed to be in the inheritance tree of
The “base class” of an instruction is the lowest class in its inheritance tree that the object should be considered entirely compatible with for _all_ circuit applications. This typically means that the subclass is defined purely to offer some sort of programmer convenience over the base class, and the base class is the “true” class for a behavioural perspective. In particular, you should not override
base_class if you are defining a custom version of an instruction that will be implemented differently by hardware, such as an alternative measurement strategy, or a version of a parametrised gate with a particular set of parameters for the purposes of distinguishing it in a
Target from the full parametrised gate.
This is often exactly equivalent to
type(obj), except in the case of singleton instances of standard-library instructions. These singleton instances are special subclasses of their base class, and this property will return that base. For example:
>>> isinstance(XGate(), XGate) True >>> type(XGate()) is XGate False >>> XGate().base_class is XGate True
In general, you should not rely on the precise class of an instruction; within a given circuit, it is expected that
Instruction.name should be a more suitable discriminator in most situations.
The classical condition on the instruction.
Get Clbits in condition.
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
Return definition in terms of other basic gates.
Get the duration.
Return instruction label
Is this instance is a mutable unique instance or not.
If this attribute is
False the gate instance is a shared singleton and is not mutable.
Return the name.
Return the number of clbits.
Return the number of qubits.
return instruction params.
Get the time unit of duration.
Return the adjoint of the unitary.
Invert this instruction.
If the instruction is composite (i.e. has a definition), then its definition will be recursively inverted.
Special instructions inheriting from Instruction can implement their own inverse (e.g. T and Tdg, Barrier, etc.)
a fresh instruction for the inverse
CircuitError – if the instruction is not composite and an inverse has not been implemented for it.
Isometry parameter has to be an ndarray.