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ffsim 0.0.75.dev0
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ffsim 0.0.75.dev0

This project is part of the Qiskit ecosystem

  • Installation
  • Tutorials
    • Implementing Trotter simulation of the double-factorized Hamiltonian
  • Explanations
    • State vectors and gates
    • Hamiltonians
    • Variational ansatzes
    • Orbital rotations
    • Double-factorized representation of the molecular Hamiltonian
    • Diagonal Coulomb Hamiltonians
    • The local unitary cluster Jastrow (LUCJ) ansatz
    • The FermionOperator class
    • Protocols
    • Qubit gate decompositions of fermionic gates
  • How-to guides
    • Sample from state vectors
    • Compute expectation values
    • Simulate the variational quantum eigensolver (VQE)
    • Simulate Trotterized time evolution for the molecular Hamiltonian
    • Simulate Trotterized time evolution for the Fermi-Hubbard model
    • Simulate entanglement forging
    • Sample from Slater determinants
    • Build Qiskit circuits for the LUCJ ansatz
    • Build Qiskit circuits for Trotterized Hamiltonian simulation
    • Simulate excitation-preserving Qiskit circuits
    • Merge orbital rotations in Qiskit circuits
  • API reference
    • ffsim
      • ffsim.apply_diag_coulomb_evolution
      • ffsim.apply_fsim_gate
      • ffsim.apply_fswap_gate
      • ffsim.apply_givens_rotation
      • ffsim.apply_hop_gate
      • ffsim.apply_num_interaction
      • ffsim.apply_num_num_interaction
      • ffsim.apply_num_op_prod_interaction
      • ffsim.apply_num_op_sum_evolution
      • ffsim.apply_on_site_interaction
      • ffsim.apply_orbital_rotation
      • ffsim.apply_quad_ham_evolution
      • ffsim.apply_tunneling_interaction
      • ffsim.DiagonalCoulombHamiltonian
      • ffsim.DoubleFactorizedHamiltonian
      • ffsim.MolecularHamiltonian
      • ffsim.MolecularHamiltonianSpinless
      • ffsim.SingleFactorizedHamiltonian
      • ffsim.init_cache
      • ffsim.MolecularData
      • ffsim.FermionAction
      • ffsim.FermionOperator
      • ffsim.ccsd_generator_restricted
      • ffsim.ccsd_generator_unrestricted
      • ffsim.cre
      • ffsim.cre_a
      • ffsim.cre_b
      • ffsim.des
      • ffsim.des_a
      • ffsim.des_b
      • ffsim.doubles_excitations_restricted
      • ffsim.doubles_excitations_unrestricted
      • ffsim.fermi_hubbard_1d
      • ffsim.fermi_hubbard_2d
      • ffsim.number_operator
      • ffsim.s_minus_operator
      • ffsim.s_plus_operator
      • ffsim.s_squared_operator
      • ffsim.s_x_operator
      • ffsim.s_y_operator
      • ffsim.s_z_operator
      • ffsim.singles_excitations_restricted
      • ffsim.singles_excitations_unrestricted
      • ffsim.uccsd_generator_restricted
      • ffsim.uccsd_generator_unrestricted
      • ffsim.SupportsApplyUnitary
      • ffsim.SupportsApproximateEquality
      • ffsim.SupportsDiagonal
      • ffsim.SupportsFermionOperator
      • ffsim.SupportsLinearOperator
      • ffsim.SupportsTrace
      • ffsim.apply_unitary
      • ffsim.approx_eq
      • ffsim.diag
      • ffsim.fermion_operator
      • ffsim.linear_operator
      • ffsim.trace
      • ffsim.BitstringType
      • ffsim.ProductStateSum
      • ffsim.ReducedDensityMatrix
      • ffsim.Spin
      • ffsim.StateVector
      • ffsim.addresses_to_strings
      • ffsim.dim
      • ffsim.dims
      • ffsim.expectation_one_body_power
      • ffsim.expectation_one_body_product
      • ffsim.hartree_fock_state
      • ffsim.rdms
      • ffsim.sample_slater
      • ffsim.sample_state_vector
      • ffsim.slater_determinant
      • ffsim.slater_determinant_amplitudes
      • ffsim.slater_determinant_rdms
      • ffsim.spin_square
      • ffsim.spinful_to_spinless_rdm1
      • ffsim.spinful_to_spinless_rdm2
      • ffsim.spinful_to_spinless_vec
      • ffsim.strings_to_addresses
      • ffsim.simulate_qdrift_double_factorized
      • ffsim.simulate_trotter_diag_coulomb_split_op
      • ffsim.simulate_trotter_double_factorized
      • ffsim.GivensAnsatzOp
      • ffsim.HopGateAnsatzOperator
      • ffsim.NumNumAnsatzOpSpinBalanced
      • ffsim.UCCSDOpRestricted
      • ffsim.UCCSDOpRestrictedReal
      • ffsim.UCCSDOpUnrestricted
      • ffsim.UCCSDOpUnrestrictedReal
      • ffsim.UCJAnglesOpSpinBalanced
      • ffsim.UCJOpSpinBalanced
      • ffsim.UCJOpSpinless
      • ffsim.UCJOpSpinUnbalanced
      • ffsim.multireference_state
      • ffsim.multireference_state_prod
      • ffsim.optimize_orbitals
    • ffsim.contract
      • ffsim.contract.contract_diag_coulomb
      • ffsim.contract.contract_num_op_sum
      • ffsim.contract.contract_one_body
      • ffsim.contract.diag_coulomb_linop
      • ffsim.contract.num_op_sum_linop
      • ffsim.contract.one_body_linop
      • ffsim.contract.two_body_linop
    • ffsim.linalg
      • ffsim.linalg.GivensRotation
      • ffsim.linalg.apply_matrix_to_slices
      • ffsim.linalg.double_factorized
      • ffsim.linalg.double_factorized_t2
      • ffsim.linalg.double_factorized_t2_alpha_beta
      • ffsim.linalg.expm_multiply_taylor
      • ffsim.linalg.givens_decomposition
      • ffsim.linalg.is_antihermitian
      • ffsim.linalg.is_hermitian
      • ffsim.linalg.is_orthogonal
      • ffsim.linalg.is_real_symmetric
      • ffsim.linalg.is_special_orthogonal
      • ffsim.linalg.is_unitary
      • ffsim.linalg.lup
      • ffsim.linalg.match_global_phase
      • ffsim.linalg.modified_cholesky
      • ffsim.linalg.one_hot
      • ffsim.linalg.reduced_matrix
    • ffsim.optimize
      • ffsim.optimize.minimize_linear_method
    • ffsim.qiskit
      • ffsim.qiskit.PRE_INIT
      • ffsim.qiskit.DiagCoulombEvolutionJW
      • ffsim.qiskit.DiagCoulombEvolutionSpinlessJW
      • ffsim.qiskit.DropNegligible
      • ffsim.qiskit.FfsimSampler
      • ffsim.qiskit.GivensAnsatzOpJW
      • ffsim.qiskit.GivensAnsatzOpSpinlessJW
      • ffsim.qiskit.MergeOrbitalRotations
      • ffsim.qiskit.NumNumAnsatzOpSpinBalancedJW
      • ffsim.qiskit.NumOpSumEvolutionJW
      • ffsim.qiskit.NumOpSumEvolutionSpinlessJW
      • ffsim.qiskit.OrbitalRotationJW
      • ffsim.qiskit.OrbitalRotationSpinlessJW
      • ffsim.qiskit.PrepareHartreeFockJW
      • ffsim.qiskit.PrepareHartreeFockSpinlessJW
      • ffsim.qiskit.PrepareSlaterDeterminantJW
      • ffsim.qiskit.PrepareSlaterDeterminantSpinlessJW
      • ffsim.qiskit.SimulateTrotterDiagCoulombSplitOpJW
      • ffsim.qiskit.SimulateTrotterDoubleFactorizedJW
      • ffsim.qiskit.UCJOpSpinBalancedJW
      • ffsim.qiskit.UCJOpSpinUnbalancedJW
      • ffsim.qiskit.UCJOpSpinlessJW
      • ffsim.qiskit.ffsim_vec_to_qiskit_vec
      • ffsim.qiskit.final_state_vector
      • ffsim.qiskit.jordan_wigner
      • ffsim.qiskit.pre_init_passes
      • ffsim.qiskit.qiskit_vec_to_ffsim_vec
    • ffsim.random
      • ffsim.random.random_antihermitian
      • ffsim.random.random_density_matrix
      • ffsim.random.random_diagonal_coulomb_hamiltonian
      • ffsim.random.random_double_factorized_hamiltonian
      • ffsim.random.random_fermion_hamiltonian
      • ffsim.random.random_fermion_operator
      • ffsim.random.random_hermitian
      • ffsim.random.random_molecular_hamiltonian
      • ffsim.random.random_molecular_hamiltonian_spinless
      • ffsim.random.random_orthogonal
      • ffsim.random.random_real_symmetric_matrix
      • ffsim.random.random_special_orthogonal
      • ffsim.random.random_state_vector
      • ffsim.random.random_t2_amplitudes
      • ffsim.random.random_two_body_tensor
      • ffsim.random.random_uccsd_op_restricted
      • ffsim.random.random_uccsd_op_restricted_real
      • ffsim.random.random_uccsd_op_unrestricted
      • ffsim.random.random_uccsd_op_unrestricted_real
      • ffsim.random.random_ucj_op_spin_balanced
      • ffsim.random.random_ucj_op_spin_unbalanced
      • ffsim.random.random_ucj_op_spinless
      • ffsim.random.random_unitary
    • ffsim.testing
      • ffsim.testing.assert_allclose_up_to_global_phase
      • ffsim.testing.generate_norb_nelec
      • ffsim.testing.generate_norb_nelec_spin
      • ffsim.testing.generate_norb_nocc
      • ffsim.testing.generate_norb_spin
      • ffsim.testing.random_nelec
      • ffsim.testing.random_occupied_orbitals
  • GitHub
  • Developer guide
  • Release notes
  • Development branch docs
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API reference¶

ffsim

Top-level module where ffsim’s main functions and classes are exposed

ffsim.contract

Functions for contracting tensors and constructing linear operators

ffsim.linalg

Linear algebra utilities

ffsim.optimize

Optimization algorithms

ffsim.qiskit

Code that uses Qiskit

ffsim.random

Random sampling utilities

ffsim.testing

Testing utilities

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