Release v0.25.0

New features since last release

Breaking changes

• We explicitly disable support for PennyLane's parameter broadcasting. #317

• We explicitly remove support for PennyLane's Sum, SProd and Prod
  as observables. (#326)

Improvements

• CI builders use a reduced set of resources and redundant tests for PRs. (#319)

• Parallelize wheel-builds where applicable. (#314)

• AVX2/512 kernels are now available on Linux/MacOS with x86-64 architecture. (#313)

Documentation

• Updated ReadTheDocs runner version from Ubuntu 20.04 to 22.04 (#327)

Bug fixes

• Test updates to reflect new additions to PennyLane. (#318)

Contributors

This release contains contributions from (in alphabetical order):

Amintor Dusko, Christina Lee, Rashid N H M, Lee J. O'Riordan, Chae-Yeun Park

Release 0.24.0

New features since last release

• Add SingleExcitation and DoubleExcitation qchem gates and generators. (#289)

• Add a new dispatch mechanism for future kernels. (#291)

• Add IsingXY gate operation. (#303)

• Support qml.state() in vjp and Hamiltonian in adjoint jacobian. (#294)

Breaking changes

• Codebase is now moving to C++20. The default compiler for Linux is now GCC10. (#295)

• Minimum macOS version is changed to 10.15 (Catalina). (#295)

Improvements

• Split matrix operations, refactor dispatch mechanisms, and add a benchmark suite. (#274)

• Add native support for the calculation of sparse Hamiltonians' expectation values. Sparse operations are offloaded to Kokkos and Kokkos-Kernels. (#283)

• Device lightning.qubit now accepts a datatype for a statevector. (#290)

dev1 = qml.device('lightning.qubit', wires=4, c_dtype=np.complex64) # for single precision
dev2 = qml.device('lightning.qubit', wires=4, c_dtype=np.complex128) # for double precision

Documentation

• Use the centralized Xanadu Sphinx Theme to style the Sphinx documentation. (#287)

Bug fixes

• Fix the issue with using available clang-format version in format. (#288)

• Fix a bug in the generator of DoubleExcitationPlus. (#298)

Contributors

This release contains contributions from (in alphabetical order):
Mikhail Andrenkov, Ali Asadi, Amintor Dusko, Lee James O'Riordan, Chae-Yeun Park, and Shuli Shu

Release 0.23.0

Release 0.23.0

New features since last release

• Add generate_samples() to lightning. (#247)

• Add Lightning GBenchmark Suite. (#249)

• Support runtime and compile information. (#253)

Improvements

• Add ENABLE_BLAS build to CI checks. (#249)

• Add more clang-tidy checks and kernel tests. (#253)

• Add C++ code coverage to CI. (#265)

• Skip over identity operations in "lightning.qubit". (#268)

Bug fixes

• Update tests to remove JacobianTape. (#260)

• Fix tests for MSVC. (#264)

• Fix #include <cpuid.h> for PPC and AArch64 in Linux. (#266)

• Remove deprecated tape execution methods. (#270)

• Update qml.probs in test_measures.py. (#280)

Contributors

This release contains contributions from (in alphabetical order):
Ali Asadi, Chae-Yeun Park, Lee James O'Riordan, and Trevor Vincent

Release 0.22.1

Bug fixes

• Ensure qml.Identity kernel is registered to C++ dispatcher. (#275)

Release 0.22.0

New features since last release

• Add Docker support. (#234)

Improvements

• Update quantum tapes serialization and Python tests. (#239)

• Clang-tidy is now enabled for both tests and examples builds under Github Actions. (#237)

• The return type of StateVectorBase data is now derived-class defined. (#237)

• Update adjointJacobian and VJP methods. (#222)

• Set GitHub workflow to upload wheels to Test PyPI. (#220)

• Finalize the new kernel implementation. (#212)

Bug fixes

• Fix for OOM errors when using adjoint with large numbers of observables. (#221)

• Add virtual destructor to C++ state-vector classes. (#200)

• Fix a bug in Python tests with operations' matrix calls. (#238)

• Refactor utility header and fix a bug in linear algebra function with CBLAS. (#228)

Contributors

This release contains contributions from (in alphabetical order):

Ali Asadi, Chae-Yeun Park, Lee James O'Riordan

Release 0.21.0

New features since last release

• Add C++ only benchmark for a given list of gates. (#199)

• Wheel-build support for Python 3.10. (#186)

• C++ support for probability, expectation value and variance calculations. (#185)

Improvements

• setup.py adds debug only when --debug is given (#208)

• Add new highly-performant C++ kernels for quantum gates. (#202)

The new kernels significantly improve the runtime performance of PennyLane-Lightning
for both differentiable and non-differentiable workflows. Here is an example workflow
using the adjoint differentiation method with a circuit of 5 strongly entangling layers:

import pennylane as qml
from pennylane import numpy as np
from pennylane.templates.layers import StronglyEntanglingLayers
from numpy.random import random
np.random.seed(42)
n_layers = 5
n_wires = 6
dev = qml.device("lightning.qubit", wires=n_wires)

@qml.qnode(dev, diff_method="adjoint")
def circuit(weights):
    StronglyEntanglingLayers(weights, wires=list(range(n_wires)))
    return [qml.expval(qml.PauliZ(i)) for i in range(n_wires)]

init_weights = np.random.random(StronglyEntanglingLayers.shape(n_layers=n_layers, n_wires=n_wires))
params = np.array(init_weights,requires_grad=True)
jac = qml.jacobian(circuit)(params)

The latest release shows improved performance on both single and multi-threaded evaluations!

• Ensure debug info is built into dynamic libraries. (#201)

Documentation

• New guidelines on adding and benchmarking C++ kernels. (#202)

Bug fixes

• Update clang-format version (#219)

• Fix failed tests on Windows. (#218)

• Fix failed tests for the non-binary wheel. (#213)

• Add virtual destructor to C++ state-vector classes. (#200)

Contributors

This release contains contributions from (in alphabetical order):

Ali Asadi, Amintor Dusko, Chae-Yeun Park, Lee James O'Riordan

Release v0.20.2

• Introduce CY kernel to Lightning to avoid issues with decomposition & adjoint. (#203)

Release 0.20.1

Bug fixes

• Fix missing header-files causing build errors in algorithms module.
  (#193)

• Fix failed tests for the non-binary wheel.
  (#191)

Release 0.20.0

What's Changed

• Add Multi-threaded DOTC, GEMV, GEMM along with BLAS Support by @maliasadi in #155
• Update PL-Lightning to support new features in PL by @maliasadi in #179
• Fix missing header for dependent packages by @mlxd in #180
• setup.py uses CMake by @chaeyeunpark in #176
• Disable AVX default for PPC and ARM by @chaeyeunpark in #182
• No init module use for the tests by @antalszava in #184
• Gate Aggregate Performance Tests; Issue #158 by @isschoch in #165
• Add VJP support to PL-Lightning by @maliasadi in #181
• Add np.complex64 support in PL-Lightning by @maliasadi in #177

New Contributors

• @Jaybsoni made their first contribution in #159
• @isschoch made their first contribution in #165

Release 0.19.0

What's Changed

• Update to development version 0.19 by @trbromley in #150
• Fix C++ compiler warnings by @maliasadi in #147
• Ensure Lightning adheres to C++17 modernization standard with clang-tidy by @mlxd in #153
• Add check-tidy to Makefile by @maliasadi in #156
• Optimise x86_64 builds with AVX friendly opts by @mlxd in #157
• Version Bump 0.19.0 by @github-actions in #163
• Fix OpenMP library issues on M1 Macs by @mlxd in #166
• Fix CI builder release issues by @mlxd in #168

New Contributors

• @github-actions made their first contribution in #163

Full Changelog: v0.18.0...v0.19.0