qiskit-addon-sqd-hpc

This repository contains an HPC-ready implementation of the Qiskit addon for Sample-based Quantum Diagonalization (SQD).

Features

• Modern C++17 template library, compatible with standard (STL) interfaces.
• Provides low-level functions for performing postselection, subsampling, and configuration recovery.
• Able to integrate with the sbd eigensolver, which was developed at RIKEN to enable large-scale SQD calculations. See the Qiskit 2.2 C API demo repository, in which a single binary harnessing both OpenMP and MPI-level parallelism is compiled for an HPC cluster.
• Cross-architecture, tested on x86_64 and ARMv8. Cross-platform, tested on Linux, macOS, and Windows, using GCC, Clang, and MSVC.
• Compile with exceptions enabled or disabled -- your choice. RTTI is optional, too.
• Complete API documentation.
• Fully tested, with a test suite based on doctest.
• Performant, with a micro-benchmark suite based on nanobench.

Documentation

All documentation is available at https://qiskit.github.io/qiskit-addon-sqd-hpc/.

How to build

The library itself consists only of header files, so it can be used regardless of build system. The tests and benchmarks are meant to be compiled with cmake.

Clone dependencies for testing

To clone repositories needed for tests and benchmarks, run:

git submodule update --init --recursive

Compile

mkdir -p build
cd build
cmake ..
cmake --build . -j4

If you wish to use a different build system, pass the -G option to the first invocation of cmake. For instance, to use ninja, run cmake .. -G Ninja.

To compile with a version of C++ later than C++17, one must pass the -DCMAKE_CXX_STANDARD option to the first invocation of cmake. For instance, to compile with the C++20 standard, run cmake .. -DCMAKE_CXX_STANDARD=20.

To compile with both RTTI and exceptions disabled, one must pass the appropriate flags to cmake. For instance:

mkdir -p build
cd build
cmake .. -DCMAKE_CXX_FLAGS="-fno-rtti -fno-exceptions -DQKA_SQD_DISABLE_EXCEPTIONS=1 -DDOCTEST_CONFIG_NO_EXCEPTIONS_BUT_WITH_ALL_ASSERTS"
cmake --build . -t sqd_tests

The above example builds only the sqd_tests target, as the benchmarks cannot be compiled with exceptions disabled because nanobench uses RTTI and exceptions internally.

Run test suite

To run the test suite, navigate to the build directory, then run

./sqd_tests

Run benchmark suite

To run the benchmark suite, navigate to the build directory, then run

./sqd_benchmarks

Deprecation policy

We follow semantic versioning and are guided by the principles in Qiskit's deprecation policy. We may occasionally make breaking changes in order to improve the user experience. When possible, we will keep old interfaces and mark them as deprecated, as long as they can co-exist with the new ones. Each substantial improvement, breaking change, or deprecation will be documented in the release notes.

Contributing

The source code is available on GitHub.

The developer guide is located at CONTRIBUTING.md in the root of this project's repository. By participating, you are expected to uphold Qiskit's code of conduct.

We use GitHub issues for tracking requests and bugs.

License

Apache License 2.0