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Introduction to debugging tools

You can test your quantum programs by running them on simulated devices and exploring their performance under realistic device noise models. This allows you to debug them before sending them to a quantum processing unit (QPU).

Quantum simulators can be used to help develop and test programs before fine-tuning them and sending them to quantum hardware. Local simulators can do this with good performance and efficiency.

Because the cost of classically simulating quantum circuits scales exponentially with the number of qubits, circuits that are larger than 50 qubits or so generally cannot run on simulators. For such circuits, you can:

  • Test smaller versions of the circuits that can be simulated classically.
  • Modify the circuits so that they become classically simulable, although less accurate.

Stabilizer circuits, also known as Clifford circuits, are a useful tool for accomplishing this latter goal. These are a restricted class of quantum circuits that can be efficiently simulated classically. Specialized simulators can easily simulate stabilizer circuits with thousands of qubits. See Efficient simulation of stabilizer circuits with Qiskit Aer primitives for more information.

For general quantum circuits, the following tools are available to test and debug your quantum programs:


Hardware considerations

Several factors impact how much memory quantum simulation requires, so there are no exact hardware requirements for simulation, but there are some guidelines you can follow.

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