Qiskit Pocket Guide

Chapter 8. Qiskit Circuit Library Standard Operations

The Qiskit Circuit Library (module qiskit.circuit.library) contains many operations and circuits that may be used as building blocks for implementing quantum algorithms. Here are some standard operations categorized as instructions, single-qubit gates, and multiqubit gates.

Standard Instructions

The standard instruction classes implement quantum operations that aren’t necessarily unitary. They are subclasses of the Instruction class (see “The Instruction Class”).

Barrier

The Barrier class creates a barrier instruction (see “Creating a barrier”) with a given number of qubits. A barrier provides both visual and functional separation between gates on a wire in a quantum circuit:

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Barrier(num_qubits)

Measure

The Measure class creates a measurement instruction for measuring a quantum state in the computational basis, placing the binary result in a classical register (see “Measuring a quantum circuit”):

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Measure()

Reset

The Reset class creates a reset instruction that resets the qubit state to $|0\rangle$ (see “Using the reset() method”):

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Reset()

Standard Single-Qubit Gates

The standard single-qubit gates implement unitary quantum operations. ...