Changelog

Deprecated

• Convert the MCX functions to gates (#4082)
• Deprecate some unneeded methods of QuantumState (#4075)
• Cleanup quantum_info.random (#4058)
• generalize dag.compose_back(), deprecate dag.extend_back() (#3772)
• Add measure probability functions to QuantumState classes (#3952)
• Command/Inst refactor: FrameChange -> ShiftPhase (#3893)
• Improves OneQubitEulerDecomposer class and add RR basis decomposition. (#3703)
• Simplify BaseOperator abstract class (#3875)
• Defaults in TranspileConfig (now called PassManagerConfig) (#3035)

Added

• Add SparsePauliOp operator class (#3932)
• add circuit.num_nonlocal_gates (#4101)
• Optimized clifford synthesis for up to 3 qubits (#4098)
• QuantumVolume and FourierChecking in circuit library (#4102)
• add a name attribute to CouplingMap (#4103)
• Add diamond norm function for quantum channels (#4050)
• Add random Clifford and pauli table functions (#4062)
• Log time for execute steps (#3922)
• Cleanup quantum_info.random (#4058)
• Add Clifford operator class (#3938)
• Add measure and reset methods to QuantumState classes (#4041)
• Add env variable and user config option to suppress packaging warnings (#3362)
• Rename sample_measure to sample_counts and sample_memory (#4056)
• Update Statevector and DensityMatrix evolve to work with operator qargs attr (#3983)
• Jupyter widget for circuit library (#3861)
• Add sample_measure to Statevector and DensityMatrix (#3987)
• Add measure probability functions to QuantumState classes (#3952)
• Add StabilizerTable class (#3931)
• add iswap and dcx gates (#3992)
• Add PauliTable symplectic operator class (#3889)
• Add num_qubits attribute to QuantumState and BaseOperator (#3986)
• Allow generic callable to be inserted in CmdDef (#3385)
• Text drawer support for open controlled gates (#3867)
• Add library of gates with their equivalent circuit implementations. (#3946)
• Add ability to add operators on subsystems. (#3888)
• Implement the RYY gate (#3912)
• Add BaseJob status methods (#3723)
• Add ScalarOp to quantum_info.operators (#3887)
• Revert "Add ScalarOp to quantum_info.operators (#3887)"
• Add ScalarOp to quantum_info.operators (#3887)
• Add qargs property, __call__, method to set qargs to BaseOperators (#3873)
• Add support for backend.run to FakeBackend (#3890)
• Add wait_for_final_state() to BaseJob (#3731)
• start of a circuit library (#3841)
• Support Scheduler in execute pipeline (#3792)

Changed

• Upgrading bind_parameters: allow in place and mixed floats + parameters (#4037)
• Optional parameter basis_gates in Optimize1qGates (#4019)
• Remove marshmallow from RunConfig (#4096)
• Support for circuit.draw(initial_state=False) (#4068)
• Implement multi-controlled U1 as gate (#3883)
• Transpiler should raise when conflicting parameters, not just ignore them silently (#4060)
• layout_method and routing_method selectors in transpile() (#3999)
• Clean up default class atol and rtol for operators and states (#3989)
• Command/Inst refactor: Pulses and Play (#3936)
• set depth/width for LookaheadSwap pass (#3996)
• Populate equivalence library with existing gate definitions. (#3979)
• Command/Inst refactor: Acquire (and Kernel, Discriminator) (#3935)
• Fix preset pass managers to not always decompose Swaps (#3963)
• fix issue 3733 making result.get_counts() return also a list of dicts (#3751)
• Command/Inst refactor: FrameChange -> ShiftPhase (#3893)
• Command/Inst refactor: Snapshot (#3933)
• Allow list params in Instruction (#3955)
• Transition DAGCircuit to retworkx (#3916)
• Command/Inst refactor: Delay (#3924)
• Remove marshmallow from Qobj (#3383)
• Switch DAGCircuit wires property to a set instead of a list (#3934)
• Use CSPLayout in Level 2 and Level 3 (#3391)
• Command/Instruction unification (#3862)
• Improves OneQubitEulerDecomposer class and add RR basis decomposition. (#3703)
• Simplify BaseOperator abstract class (#3875)
• remove identity insertion in gate decomposition (#3879)
• Docathon: schedule.py and remove deprecated buffer arg (#3836)
• Defaults in TranspileConfig (now called PassManagerConfig) (#3035)

Removed

• Remove deprecated code! :) (#4005)
• Remove warnings about dt, dtm, and rep_time units changing (#3981)
• Remove previously deprecated instruction parameter types (#3948)

Fixed

• Add LookaheadSwap condition to prevent hangs (#4112)
• Optimize1qGates should allow rounding when calculating theta (#4015)
• BarrierBeforeFinalMeasurements pass to insert device-wide barrier. (#4054)
• Bugfix: Instruction name / pulse library name mismatch (#4051)
• Each thread needs its own passmanager (#4003)
• Update dt and dtm for FakeAlmaden: it had 'dt' and 'dtm' in units of seconds, but the spec has them in units of ns. (#3991)
• Fix pulse drawer bug for plot range (#3954)
• Fix schedule assember bug (#3900)
• Instruction.copy to deepcopy self._definition if it is set. (#3874)
• Creates dag op for a call of QASM custom gate (#3393)
• Fix substitute parameters when decomposing composite gates (#3914)
• Fixed issue #3806 by checking if QuantumCircuit args can be cast to int (#3869)
• Fix circuit extending with self (#3843)