HI!
Yesterday I wrote on the MResetZ() which allows us to get the status of a Qubit and release it. Well, at the end of each Q# operation, all the used Qubits need to be released for the simulator to work properly.
The following sample code will show a bad sample where a Qubit is used and not released correctly:
operation HGateWithOutReset (initial: Result) : (Result) | |
{ | |
body | |
{ | |
mutable res = Zero; | |
using (qubits = Qubit[2]) | |
{ | |
let qubit1 = qubits[0]; | |
let qubit2 = qubits[1]; | |
H(qubit1); | |
set res = M(qubit1); | |
} | |
return (res); | |
} | |
} |
So, in runtime we will find this amazing and cool error:
Microsoft.Quantum.Simulation.Simulators.Exceptions.ReleasedQubitsAreNotInZeroState
HResult=0x80131500
Message=Released qubits are not in zero state.
Source=Microsoft.Quantum.Simulation.Simulators
Microsoft Quantum Development Kit offers us a series of operations that help us to release Qubits: Reset() and ResetAll(). As its name indicates Reset() is intended to release a single Qubit and ResetAll() to release an array of Qubits.
Given a single Qubit, Reset() evaluates the Qubit state and ensures that the Qubit is in the state |0⟩ so it can be safely released.
The following 2 operations show examples of how to use these operations
operation HGateWithResetEachQubit (initial: Result) : (Result) | |
{ | |
body | |
{ | |
mutable res = Zero; | |
using (qubits = Qubit[2]) | |
{ | |
let qubit1 = qubits[0]; | |
let qubit2 = qubits[1]; | |
H(qubit1); | |
set res = M(qubit1); | |
Reset(qubit1); | |
Reset(qubit2); | |
} | |
return (res); | |
} | |
} | |
operation HGateWithResetAllQubits (initial: Result) : (Result) | |
{ | |
body | |
{ | |
mutable res = Zero; | |
using (qubits = Qubit[2]) | |
{ | |
let qubit1 = qubits[0]; | |
let qubit2 = qubits[1]; | |
H(qubit1); | |
set res = M(qubit1); | |
ResetAll(qubits); | |
} | |
return (res); | |
} | |
} |
Happy QCoding!
Greetings @ Toronto
El Bruno
References
- Microsoft Quantum Development Kit
- Q# Reference, M operation
- Q# Reference, H operation
- Q# Reference, MResetZ operation
- Q# Reference, Reset operation
- Q# Reference, ResetAll operation
My Posts
- El Bruno, Using MResetZ() to reset Qubits in Q#
- El Bruno, Qubit operations in Q#
- El Bruno, Information about Simulators on Microsoft Quantum Development Kit (Do you have 16 TB RAM?)
- El Bruno, Hello QWorld using Microsoft #Quantum Development Kit (fix to build the project) [Updated]
- El Bruno, More information about the Microsoft bet in Quantum Computing
- El Bruno, Quantum Computing, let’s add this one to Artificial Intelligence and Mixed Reality!