started features list

FEATURES.rst

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+This page contains a partial list of important functionality currently implemented
+in OpenFermion and its plugins.
+
+
+OpenFermion core functionality
+==============================
+
+Transforms
+----------
+
+* Standard Jordan-Wigner transform: method for mapping FermionOperators to QubitOperators.
+
+* Optimized molecular Jordan-Wigner transform: numerically performant method of applying
+  Jordan-Wigner to InteractionOperator that is specialized for two-body number-conserving operators.
+
+* Reverse Jordan-Wigner transform: method for mapping QubitOperators to FermionOperators.
+
+* Bravyi-Kitaev transform: method for mapping FermionOperators to QubitOperators with
+  logarithmic many-body order. Implementation from arXiv:1208.5986.
+
+* Bravyi-Kitaev Fenwick tree transform: method for mapping FermionOperators to QubitOperators with
+  logarithmic many-body order basedon Fenwick Trees. Implementation from arXiv:1701.07072.
+
+* Bravyi-Kitaev Superfast transform: method for mapping FermionOperators to QubitOperators
+  with constant many-body order. Number of qubits required scales as number of terms.
+  Implementation from arXiv:1712.00446.
+
+* Verstraete-Cirac transform: maps a FermionOperator on a d-dimensional lattice to a
+  QubitOperator on a d-dimensional lattice with twice as many degrees of freedom.
+  Implementation from arXiv:cond-mat/0508353.
+
+* Fermion transforms from binary codes: generalized machinery for implementing an
+  arbitrary (possibly non-linear) fermion transform (and decoding). Can be used to reduce
+  qubit requirements by exploiting symmetries in FermionOperator.
+  Implementation from arXiv:1712.07067.
+
+* Routines for converting between InteractionOperator, QuadraticHamiltonian,
+  FermionOperator, QubitOperator as well sparse matrix representations.
+
+
+Hamiltonians
+------------
+
+* Fermi-Hubbard model: generate Fermi-Hubbard models as FermionOperators.
+  Can generate in 1D or 2D, with or without chemical potential and/or magnetic field,
+  with or without particle/hole symmetry, with or without periodic boundary conditions,
+  and with or without spin.
+
+* Plane wave Hamiltonian: generate molecule electronic structure Hamiltonians
+  in the plane wave basis. Can generate with an arbitrary nuclear potential, with
+  nuclei having arbitrary spins at arbitrary lattice sites. Can choose basis by
+  an energy cutoff or by taking frequencies on a grid. Can generate in 1D, 2D or 3D.
+  Can generate with or without spins.
+
+* Dual basis Hamiltonian: generate molecule electronic structure Hamiltonians
+  in the plane wave dual basis from arXiv:1706.00023. Can generate with an arbitrary
+  nuclear potential, with nuclei having arbitrary spins at arbitrary lattice sites.
+  Can generate in 1D, 2D or 3D. Can generate with or without spins.
+
+* Jellium Hamiltonian: can generate in the plane wave or dual formalism with all
+  of the options for those basis sets mentioned above.
+
+* Mean-field D-Wave Hamiltonian: can generate the Hamiltonian for BCS mean-field
+  description of superconductivity. Can generate in 1D or 2D, with or without
+  chemical_potential, with or without periodic boundary conditions and with
+  adjustable superconducting gap and tunneling parameters.
+
+* Generate atomic rings: can automatically generate initial MolecularData
+  for atomic rings with variable atom spacing, basis, ring size and atom type.
+
+* Generate atomic lattices: can automatically generate initial MolecularData
+  for atomic lattices in 1D, 2D or 3D with variable atom spacing, lattice size and atom type.
+
+* Generate atoms: can automatically generate initial MolecularData
+  for single atom calculations. Function chooses the correct spin assignment automatically.
+  Can generate for first half of periodic table with any basis set.
+
+
+Core Data Structures
+--------------------
+
+* SymbolicOperator: A weighted sum of terms, each of which is a product of factors specifying
+  an index (a non-negative integer) and an action on that index.
+  Parent class of FermionOperator and QubitOperator.
+
+* FermionOperator: A sum of products of fermionic ladder operators.
+
+* QubitOperator: A sum of products of Pauli operators.
+
+* MolecularData: Structure for storing electronic structure calculations on molecules.
+
+* PolynomialTensor: Efficient tensor representation of an operator that corresponds
+  with a multilinear polynomial in the fermionic ladder operators.
+  Parent class of InteractionOperator, InteractionRDM, and QuadraticHamiltonian.
+
+* InteractionOperator: A numerically performant class for storing 2-body operators.
+
+* InteractionRDM: A numerically performant class for storying 2-body RDMs
+
+* QuadraticHamiltonian: A Hamiltonian that is quadratic in the fermionic ladder operators.
+
+* CodeOperator:
+
+* BinaryOperator:
+
+
+Utilities
+---------
+
+* Special fermion operators: helper functions generate Sz, S+, S-, S^2, majorana and number operators.
+
+* Slater determinants: compile quantum circuits for preparing Slater determinants and
+  fermionic Gaussian states using Givens rotations
+
+* BCH expansion: compute the logarithm of a product of exponentials of operators
+  up to a specified order using the Baker-Campbell-Hausdorff formula
+
+
+Measurements
+------------
+
+* Generate RDM Equality Constraints:
+
+* RDM Equality Constraint Projection:
+
+
+OpenFermion-PySCF
+=================
+
+
+OpenFermion-Psi4
+================
+
+
+OpenFermion-ProjectQ
+====================
+
+
+Forest-OpenFermion
+==================