Utils Submodule

This submodule contains utility functions used throughout pydmqmc. While accessible to users, these functions are generally less polished than the rest of pydmqmc.

Bitarray Manipulation 

`pydmqmc.utils.bitarray_to_integer`(ba)	Generate the integer representation of a given bitarray.
`pydmqmc.utils.integer_to_bitarray`(iba, norb)	Generate a bitarray given an integer representation.
`pydmqmc.utils.concate_bitarrays_to_label`(...)	Concatenate two bitarrays and then convert to integer representation.
`pydmqmc.utils.extract_bitarrays_from_label`(...)	Extract the bitarrays used to generate a given integer state label.
`pydmqmc.utils.get_nex`(b1, b2)	Return the number of excitations between two states.
`pydmqmc.utils.get_occ`(b1)	Return the number of occupied orbitals in a given bitarray.
`pydmqmc.utils.get_iocc`(occ, orb)	Return the index of an orbital within the set of occupied orbitals.
`pydmqmc.utils.get_single_perm`(b1, a, r, nel)	Return new bitarray and the number of permutations for a single excitation.
`pydmqmc.utils.get_double_perm`(b1, a, b, r, ...)	Return new bitarray and the number of permutations for a double excitation.
`pydmqmc.utils.get_ex_info`(b1, b2, nel)	Return information on the excitations between two states.

Integrators 

`pydmqmc.utils.euler`(func, y, dt[, ph_dummy])	Update y using Euler's method.
`pydmqmc.utils.parallel_euler`(func, y, dt, ...)	Update y using Euler's method.
`pydmqmc.utils.rk4`(func, y, dt[, ph_dummy])	Update y using the fourth-order Runge-Kutta method.
`pydmqmc.utils.parallel_rk4`(func, y, dt, ph, ...)	Update y using the fourth-order Runge-Kutta method.

Parallelism Support 

pydmqmc.utils.ParallelHelper(shape)

Helper for coordinating parallel Methods.

Permutations 

pydmqmc.utils.generate_ijab_symmetries_array(i, ...)

Generate an array of valid symmetry permutations of the orbital indicies.

Point Group Symmetry 

`pydmqmc.utils.pg_sym_cross_prod`(sym1, sym2, mask)	Cross product of two point group symmetries.
`pydmqmc.utils.pg_sym_conj`(sym, mask)	Conjugate of a point group symmetry.
`pydmqmc.utils.orb_sym`(orb_syms, mask)	Construct the symmetry of a determinant from its orbitals.

Saving Data 

`pydmqmc.utils.save_array`(data, basename[, ...])	Save an array as a chosen file type.
`pydmqmc.utils.save_report`(list_of_dicts, ...)	Save a lists of dictionaries as a chosen file type.

Slater-Condon Rules 

`pydmqmc.utils.sc0`(ba, sys)	Hamiltonian matrix element between a state and itself.
`pydmqmc.utils.sc1`(ba, a, r, perms, sys)	Hamiltonian matrix element between singly excited states.
`pydmqmc.utils.sc2`(a, b, r, s, perms, sys)	Hamiltonian matrix element between doubly excited states.