API Reference

In this section we present the main Qibo components and primitives included in the public API.

• Models
  • Circuit models
    • Circuit
    • Circuit addition
    • Circuit fusion
    • Quantum Fourier Transform (QFT)
    • Variational Quantum Eigensolver (VQE)
    • Adiabatically Assisted Variational Quantum Eigensolver (AAVQE)
    • Quantum Approximate Optimization Algorithm (QAOA)
    • Feedback-based Algorithm for Quantum Optimization (FALQON)
    • Grover’s Algorithm
    • Iterative Quantum Amplitude Estimation (IQAE)
  • Time evolution
    • State evolution
    • Adiabatic evolution
  • Data Encoders
    • Binary encoder
    • Computational Basis Encoder
    • Dicke state
    • Entangling layer
    • Greenberger-Horne-Zeilinger (GHZ) state
    • Graph state
    • Fixed Hamming-weight Encoder
    • Permutation synthesis
    • Phase Encoder
    • Sparse encoder
    • Unary Encoder
    • Unary Encoder for Random Gaussian States
    • Up-to-Hamming-weight-\(k\) Encoder
  • Error Mitigation
    • Readout Mitigation
    • Response Matrix
    • Randomized readout mitigation
    • Zero Noise Extrapolation (ZNE)
    • Clifford Data Regression (CDR)
    • Variable Noise CDR (vnCDR)
    • Importance Clifford Sampling (ICS)
• Gates
  • Abstract gate
    • Gate
  • Single qubit gates
    • Hadamard (H)
    • Pauli X (X)
    • Pauli Y (Y)
    • Pauli Z (Z)
    • Square-root of Pauli X (SX)
    • S gate (S)
    • T gate (T)
    • Identity (I)
    • Align (A)
    • Measurement (M)
    • Rotation X-axis (RX)
    • Rotation Y-axis (RY)
    • Rotation Z-axis (RZ)
    • First general unitary (U1)
    • Second general unitary (U2)
    • Third general unitary (U3)
  • Two qubit gates
    • Controlled-NOT (CNOT)
    • Controlled-Y (CY)
    • Controlled-phase (CZ)
    • Controlled-Hadamard (CH)
    • Controlled-Square Root of X (CSX)
    • Controlled-rotation X-axis (CRX)
    • Controlled-rotation Y-axis (CRY)
    • Controlled-rotation Z-axis (CRZ)
    • Controlled first general unitary (CU1)
    • Controlled second general unitary (CU2)
    • Controlled third general unitary (CU3)
    • Swap (SWAP)
    • iSwap (iSWAP)
    • Square root of iSwap (SiSWAP)
    • f-Swap (FSWAP)
    • fSim
    • Sycamore gate
    • fSim with general rotation
    • Parametric XX interaction (RXX)
    • Parametric YY interaction (RYY)
    • Parametric ZZ interaction (RZZ)
    • Parametric ZX interaction (RZX)
    • Parametric XX-YY interaction (RXXYY)
    • Givens gate
    • Reconfigurable Beam Splitter gate (RBS)
    • Echo Cross-Resonance gate (ECR)
  • Special gates
    • Toffoli
    • CCZ
    • Deutsch
    • Fan-out
    • Generalized Reconfigurable Beam Splitter (RBS)
    • Arbitrary unitary
    • Callback gate
    • Fusion gate
  • IONQ Native gates
    • GPI
    • GPI2
    • Mølmer–Sørensen (MS)
  • Quantinuum native gates
    • U1q
  • IQM native gates
    • Phase-\(RX\)
• Channels
  • Kraus channel
    • KrausChannel
  • Unitary channel
    • UnitaryChannel
  • Pauli noise channel
    • PauliNoiseChannel
  • Depolarizing channel
    • DepolarizingChannel
  • Thermal relaxation channel
    • ThermalRelaxationChannel
  • Amplitude damping channel
    • AmplitudeDampingChannel
  • Phase damping channel
    • PhaseDampingChannel
  • Readout error channel
    • ReadoutErrorChannel
  • Reset channel
    • ResetChannel
• Noise
  • NoiseModel
    • NoiseModel.add()
    • NoiseModel.apply()
  • Quantum errors
    • KrausError
    • UnitaryError
    • PauliError
    • DepolarizingError
    • ThermalRelaxationError
    • AmplitudeDampingError
    • PhaseDampingError
    • ReadoutError
    • ResetError
    • CustomError
  • IBMQ noise model
    • IBMQNoiseModel
• Hamiltonians
  • AbstractHamiltonian
    • AbstractHamiltonian.matrix
    • AbstractHamiltonian.eigenvalues()
    • AbstractHamiltonian.eigenvectors()
    • AbstractHamiltonian.ground_state()
    • AbstractHamiltonian.exp()
    • AbstractHamiltonian.expectation()
    • AbstractHamiltonian.expectation_from_state()
  • Matrix Hamiltonian
    • Hamiltonian
  • Symbolic Hamiltonian
    • SymbolicHamiltonian
  • Non-interacting Pauli-X
    • X
  • Non-interacting Pauli-Y
    • Y
  • Non-interacting Pauli-Z
    • Z
  • Ising model
    • Ising
  • Transverse-field Ising model
    • TFIM
  • Max Cut
    • MaxCut
  • LABS
    • LABS
  • Fermi-Hubbard model
    • FermiHubbard
  • Heisenberg model
    • Heisenberg
  • Heisenberg XXX
    • XXX
  • Heisenberg XXZ
    • XXZ
  • Graph Partitioning Problem
    • GPP
• Symbols
  • Symbol
    • Symbol.gate
    • Symbol.full_matrix()
  • I
  • X
  • Y
  • Z
• Execution Outcomes
  • QuantumState
    • QuantumState.symbolic()
    • QuantumState.state()
    • QuantumState.probabilities()
    • QuantumState.to_dict()
    • QuantumState.dump()
    • QuantumState.from_dict()
    • QuantumState.load()
  • MeasurementOutcomes
    • MeasurementOutcomes.frequencies()
    • MeasurementOutcomes.probabilities()
    • MeasurementOutcomes.has_samples()
    • MeasurementOutcomes.samples()
    • MeasurementOutcomes.measurement_gate
    • MeasurementOutcomes.apply_bitflips()
    • MeasurementOutcomes.expectation_from_samples()
    • MeasurementOutcomes.to_dict()
    • MeasurementOutcomes.dump()
    • MeasurementOutcomes.from_dict()
    • MeasurementOutcomes.load()
    • MeasurementOutcomes.from_samples()
    • MeasurementOutcomes.from_frequencies()
  • CircuitResult
    • CircuitResult.probabilities()
    • CircuitResult.to_dict()
    • CircuitResult.from_dict()
• Callbacks
  • Callback
    • Callback.nqubits
  • Entanglement entropy
    • EntanglementEntropy
  • Norm
    • Norm
  • Overlap
    • Overlap
  • Energy
    • Energy
  • Gap
    • Gap
• Solvers
  • BaseSolver
    • BaseSolver.t
  • TrotterizedExponential
  • Exponential
  • RungeKutta4
  • RungeKutta45
• Optimizers
  • optimize()
  • cmaes()
  • newtonian()
  • sgd()
• Parameter
  • calculate_derivatives()
  • Parameter
    • Parameter.nparams
    • Parameter.nfeat
    • Parameter.ncomponents
    • Parameter.trainable_parameter_indices()
    • Parameter.unaffected_by()
    • Parameter.partial_derivative()
• Gradients
  • parameter_shift()
  • finite_differences()
• Quantum Information
  • Basis
    • Pauli basis
    • Computational basis to Pauli basis
    • Pauli basis to computational basis
  • Phase-space Representation of Stabilizer States
    • Clifford
  • Entanglement measures
    • Concurrence
    • Entanglement of formation
    • Negativity
    • Entanglement fidelity
    • Meyer-Wallach entanglement
    • Entanglement capability
  • Entropy measures
    • Shannon entropy
    • Classical relative entropy
    • Classical mutual information
    • Classical Rényi entropy
    • Classical Rényi relative entropy
    • Classical Tsallis entropy
    • Classical Tsallis relative entropy
    • von Neumann entropy
    • Relative von Neumann entropy
    • Mutual information
    • Rényi entropy
    • Relative Rényi entropy
    • Tsallis entropy
    • Relative Tsallis entropy
    • Entanglement entropy
  • Metrics
    • Purity
    • Impurity
    • Trace distance
    • Hilbert-Schmidt inner product
    • Hilbert-Schmidt distance
    • Fidelity
    • Infidelity
    • A fidelity
    • N fidelity
    • Chen fidelity
    • Geometric-mean fidelity
    • Max fidelity
    • Bures angle
    • Bures distance
    • Process fidelity
    • Process infidelity
    • Average gate fidelity
    • Gate error
    • Diamond Norm
    • Expressibility of parameterized quantum circuits
    • Frame Potential
    • Quantum Fisher Information Matrix
  • Linear Algebra Operations
    • Commutator
    • Anticommutator
    • Partial trace
    • Partial transpose
    • Matrix exponentiation
    • Matrix logarithm
    • Matrix power
    • Matrix square root
    • Singular value decomposition
    • Schmidt decomposition
    • Lanczos algorithm
  • Quantum Networks
    • QuantumNetwork
    • QuantumComb
    • QuantumChannel
  • Random Ensembles
    • Haar-random \(U_{3}\)
    • Random Gaussian matrix
    • Random Hermitian matrix
    • Random unitary matrix
    • Random quantum channel
    • Random statevector
    • Random density matrix
    • Random Clifford
    • Random Pauli
    • Random Pauli Hamiltonian
    • Random stochastic matrix
  • Superoperator Transformations
    • Vectorization
    • Unvectorization
    • To Choi
    • To Liouville
    • To Pauli-Liouville
    • To Chi
    • To Stinespring
    • Choi to Liouville
    • Choi to Pauli-Liouville
    • Choi to Kraus
    • Choi to Chi-matrix
    • Choi to Stinespring
    • Kraus to Choi
    • Kraus to Liouville
    • Kraus to Pauli-Liouville
    • Kraus to Chi-matrix
    • Kraus to Stinespring
    • Liouville to Choi
    • Liouville to Pauli-Liouville
    • Liouville to Kraus
    • Liouville to Chi-matrix
    • Liouville to Stinespring
    • Pauli-Liouville to Liouville
    • Pauli-Liouville to Choi
    • Pauli-Liouville to Kraus
    • Pauli-Liouville to Chi-matrix
    • Pauli-Liouville to Stinespring
    • Chi-matrix to Choi
    • Chi-matrix to Liouville
    • Chi-matrix to Pauli-Liouville
    • Chi-matrix to Kraus
    • Chi-matrix to Stinespring
    • Stinespring to Choi
    • Stinespring to Liouville
    • Stinespring to Pauli-Liouville
    • Stinespring to Kraus
    • Stinespring to Chi-matrix
    • Kraus operators as probabilistic sum of unitaries
  • Utility Functions
    • Hamming weight
    • Hamming distance
    • Hadamard Transform
    • Hellinger distance
    • Hellinger fidelity
    • Hellinger shot error
    • Total variation distance
    • Haar integral
    • Parameterized quantum circuit integral
    • Decompose permutation into the fewest pairwise transpositions
• Tomography
  • Gate Set Tomography
    • GST()
• Transpiler
  • Abstract classes
    • Optimizer
    • Placer
    • Router
  • Asserts
    • Assert circuit equivalence
    • Assert connectivity
    • Assert decomposition
    • Assert placement
    • Assert transpilation
  • Blocks
    • Block
    • Circuit block
    • Block decomposition
  • Decompositions
    • Gate decomposition
  • Optimizer
    • Preprocessing
    • Rearrange
  • Pipeline
    • Passes
    • Restrict qubit connectivity
  • Placer
    • Random
    • Reverse traversal
    • Subgraph
    • Star connectivity
  • Router
    • Circuit map
    • Sabre
    • Shorterst paths
    • Start connectivity
  • Unroller
    • Native gates
    • Unroller
    • Translate gate
• Parallelism
  • parallel_execution()
  • parallel_circuits_execution()
  • parallel_parametrized_execution()
• Backends
  • Backend
    • Backend.qubits
    • Backend.connectivity
    • Backend.natives
    • Backend.cast()
    • Backend.is_sparse()
    • Backend.set_device()
    • Backend.set_dtype()
    • Backend.set_seed()
    • Backend.set_threads()
    • Backend.to_numpy()
    • Backend.complex64
    • Backend.complex128
    • Backend.float32
    • Backend.float64
    • Backend.int8
    • Backend.int16
    • Backend.int32
    • Backend.int64
    • Backend.uint8
    • Backend.abs()
    • Backend.add_at()
    • Backend.all()
    • Backend.allclose()
    • Backend.angle()
    • Backend.any()
    • Backend.append()
    • Backend.arange()
    • Backend.arccos()
    • Backend.arcsin()
    • Backend.arctan2()
    • Backend.argsort()
    • Backend.array_equal()
    • Backend.ascontiguousarray()
    • Backend.block()
    • Backend.block_diag()
    • Backend.ceil()
    • Backend.concatenate()
    • Backend.conj()
    • Backend.coo_matrix()
    • Backend.copy()
    • Backend.cos()
    • Backend.count_nonzero()
    • Backend.csr_matrix()
    • Backend.cumsum()
    • Backend.default_rng()
    • Backend.delete()
    • Backend.det()
    • Backend.diag()
    • Backend.dot()
    • Backend.eig()
    • Backend.eigh()
    • Backend.eigsh()
    • Backend.eigvalsh()
    • Backend.eigvals()
    • Backend.einsum()
    • Backend.empty()
    • Backend.exp()
    • Backend.expand_dims()
    • Backend.expm()
    • Backend.flatnonzero()
    • Backend.flip()
    • Backend.floor()
    • Backend.full()
    • Backend.hstack()
    • Backend.identity()
    • Backend.imag()
    • Backend.inv()
    • Backend.isnan()
    • Backend.kron()
    • Backend.log()
    • Backend.logm()
    • Backend.log2()
    • Backend.log10()
    • Backend.matmul()
    • Backend.matrix_norm()
    • Backend.max()
    • Backend.maximum()
    • Backend.mean()
    • Backend.min()
    • Backend.minimum()
    • Backend.mod()
    • Backend.moveaxis()
    • Backend.nonzero()
    • Backend.ones()
    • Backend.outer()
    • Backend.prod()
    • Backend.qr()
    • Backend.random_choice()
    • Backend.random_integers()
    • Backend.random_normal()
    • Backend.random_sample()
    • Backend.random_uniform()
    • Backend.ravel()
    • Backend.real()
    • Backend.repeat()
    • Backend.reshape()
    • Backend.right_shift()
    • Backend.roll()
    • Backend.round()
    • Backend.searchsorted()
    • Backend.shuffle()
    • Backend.sign()
    • Backend.sin()
    • Backend.sort()
    • Backend.sqrt()
    • Backend.squeeze()
    • Backend.std()
    • Backend.sum()
    • Backend.swapaxes()
    • Backend.tanh()
    • Backend.tensordot()
    • Backend.trace()
    • Backend.transpose()
    • Backend.tril()
    • Backend.tril_indices()
    • Backend.triu()
    • Backend.unique()
    • Backend.var()
    • Backend.vector_norm()
    • Backend.vstack()
    • Backend.where()
    • Backend.zeros()
    • Backend.zeros_like()
    • Backend.eigenvalues()
    • Backend.eigenvectors()
    • Backend.jacobian()
    • Backend.matrix_exp()
    • Backend.matrix_log()
    • Backend.matrix_sqrt()
    • Backend.singular_value_decomposition()
    • Backend.maximally_mixed_state()
    • Backend.overlap_statevector()
    • Backend.plus_state()
    • Backend.reset_error_density_matrix()
    • Backend.thermal_error_density_matrix()
    • Backend.zero_state()
    • Backend.apply_channel()
    • Backend.apply_gate()
    • Backend.apply_gate_half_density_matrix()
    • Backend.collapse_state()
    • Backend.execute_circuit()
    • Backend.execute_circuits()
    • Backend.execute_circuit_repeated()
    • Backend.execute_distributed_circuit()
    • Backend.matrix()
    • Backend.matrix_parametrized()
    • Backend.matrix_fused()
    • Backend.aggregate_shots()
    • Backend.calculate_frequencies()
    • Backend.sample_frequencies()
    • Backend.sample_shots()
    • Backend.samples_to_binary()
    • Backend.samples_to_decimal()
    • Backend.exp_value_diagonal_observable_dense_from_samples()
    • Backend.exp_value_diagonal_observable_symbolic_from_samples()
    • Backend.exp_value_observable_dense()
    • Backend.exp_value_observable_symbolic()
    • Backend.exp_value_observable_symbolic_from_samples()
  • Clifford Simulation
    • CliffordBackend
  • Simulation of Hamming-weight-preserving circuits
    • HammingWeightBackend
    • HammingWeightResult
  • Cloud Backends
• Configuration
• Models for High Energy Physics
  • Quantum PDFs
    • qPDF circuit model