Changelog

Added

• Add safe Python-extension module C API headers (#15762)
• Add qk_circuit_draw function to the C API (#15361)
• New function to negate expressions (#15447)
• Add runtime-version checking qk_api_version (#15831)
• Add barrier_label_len option to circuit drawers (#15776)
• Enable parameterized gates in C (#15106)
• Implement SparseObservable.evolve (#15561)
• Add C API vtable to pyext (#15761)
• Introduce QkTranspileState in C transpile stages. (#15486)
• Add C/Python interop for QuantumRegister and ClassicalRegister (#15768)
• Add Python conversion to QkObs (#15821)
• PBC transformations for C (#15756)
• SynthesizeRZRotations pass (#15641)
• Add QkCircuit C/Python interoperation via QuantumCircuit._data (#15767)
• Separate type/constant declarations from functions in C headers (#15760)
• Rust QPY version 13 compatibility (#15663)
• Add C/Python interop for Target and DAGCircuit (#15337)
• Expose Pauli-based computation gates to C (#15754)
• Add qiskit.capi module (#15711)
• Add qk_dag_substitute_node_with_unitary to the C API (#15757)
• Transpiler pass that converts a generic circuit to PBC (#15502)
• Use PauliProductRotationGate in LitinskiTransformation (#15753)
• Add PauliProductRotationGate (#15720)
• C API function for replacing a block of nodes with a unitary gate (#15682)
• Add DAG-based variants of transpiler pass functions in C API (#15614)
• Support adding a barrier in LitinskiTransformation (#15639)
• Add Suzuki-Trotter to C API (#15459)
• Fix linear dependency on base bit count in QuantumCircuit.compose (#15696)
• RCCXGate is self-inverse (#15686)
• feat: SparseObservable addition with scalar multiplication (#15599)
• feat: in-place arithmetic for QkObs (#15598)
• Extend SubstitutePi4Rotations to 2q gates (#15483)
• Reducing the number of Clifford gates in OptimizeCliffordT (#15634)
• Add PauliLindbladMap.generators() method (#15544)
• Add RXX/RYY-based equivalence for XXMinusYYGate (#15604)
• Rewrite default UnitarySynthesis to cache decomposers (#15492)
• Add method to draw coupling map (#15114)
• Allow null pointers for zero-length slices in QkObs (#15540)
• Add SparseObservable support to evolved_operator_ansatz (#15442)
• Add pauli() accessor to PauliProductMeasurement (#15469)
• Add Clifford circuit optimization to BasicSimulator (#15159)
• Expose IQP circuit generator via C bindings (#15396)

Fixed

• Fixed commutation checking between two Pauli product measurements (backport #16023) (#16040)
• Avoid triggering register/layout warning in remove_final_measurements (#16026) (#16037)
• Fix C transpiler level 3 optimisation loop (#15967) (#16008)
• Producing correct QFT circuits over linear connectivity with 32 or more qubits (#16004) (#16007)
• Rewrite QPY ParameterExpression handling in pure Polish form (#15934) (#15961)
• Correctly enforce matrix size check in CommutationChecker (#15933) (#15936)
• QPY Rust and Python compatibility fixes (#15847) (#15887)
• Remove unwanted remapping (#15872) (#15885)
• Fix: BasisTranslator processing of nested ControlFlowOp (#15875) (#15884)
• Fix: Initialize.inverse() now raises CircuitError immediately (#15782) (#15848)
• Fix annotation-handling in Rust-space QPY (#15649)
• Don't track loop_param (#15814)
• Fix PauliEvolutionGate trace and dim calculation (#15816)
• Avoid panics in Quantum Shannon Decomposition Rust code (#15635)
• Fix QPY bug with user-defined register named 'ancilla' (#15623)
• Forbid duplicate cargs in QuantumCircuit.append (#15789)
• Fix synth_clifford_depth_lnn for single-qubit Cliffords (#15781)
• Fix linear dependency on base bit count in QuantumCircuit.compose (#15696)
• Typed iterator in QASM3 export of for loops (#15290)
• Bump minimal NumPy Version to 1.21 (#15705)
• Fix HighLevelSynthesis qubit tracking mechanism (#15685)
• Fix ParameterExpression.sympify() for RPOW operations (#15642)
• Fix MCX synthesis methods when the number of control qubits is 0 (#15672)
• Fix defining and appending multi-controlled gates with 0 control qubits. (#15673)
• Fixing QuantumCircuit.repeat with parameterized gates (#15646)
• Fix digit escaping in OpenQASM 3 identifier (#15305)
• Add check excluding BreakLoop and ContinueLoop from control flow identification (#15626)
• Fix "`BreakLoopOp' object has no attribute 'blocks" bug (#15581)
• Make docstring for Counts more precise and validate input (#8653)
• Handle zero-length permutation synthesis (#15556)
• Automatically determine coeffs type in SparsePauliOp.from_sparse_list (#15427)
• Check length of bit_terms before accessing during qk_obs_term (#15537)
• Fix plot_state_qsphere phase anchor bias due to solver noise (#15494)
• Represent non-fixed params as NaN for QkTargetOp (#15463) (#15525)
• Represent non-fixed params as NaN for QkTargetOp (#15463)
• Fix param extraction for arrays with a single element (backport #15436) (#15522)
• Fix param extraction for arrays with a single element (#15436)
• Add SparseObservable support to evolved_operator_ansatz (#15442)

Changed

• Enable parameterized gates in C (#15106)
• Add Python conversion to QkObs (#15821)
• Add QkCircuit C/Python interoperation via QuantumCircuit._data (#15767)
• Update Linux build image to manylinux_2_28 (#15791)
• Use PauliProductRotationGate in LitinskiTransformation (#15753)
• Replace bincode with binrw in basic_approximations serialization (#15693)
• Pivot to using ruff for all linting (#15603)
• Use QkParam as parameters for QkTargetOp. (#15538)
• Remove deprecated QISKIT_VERSION_NUMERIC symbol (#15518)

Deprecated

• Deprecate qk_transpiler_standalone_optimize_1q_sequences (#15627)

Removed

• Follow through on MCMT deprecations (#15606)

Build System

• Update Linux build image to manylinux_2_28 (#15791)
• Add qiskit.capi module (#15711)
• Move cbindgen logic into separate crate (#15679)
• Replace requirements-*.txt with PEP 735 dependency groups (#15619)
• Relax required version of CMake (#15653)
• Expose default build profile as QISKIT_BUILD_PROFILE (#15242)