2.9. HORTON dictionary of variables¶

For a full list of class names and variables, consult the Index.

2.9.1. Rules¶

The following naming rules are used in the HORTON source code:

• Lower and upper case is used according to PEP8. In share: CamelCase for class names, lower_case for anything else. In lower-case names, underscore may be used to improve readability. For details, see: http://legacy.python.org/dev/peps/pep-0008/#prescriptive-naming-conventions.
• Except for local variables inside one function or method, variable names should at least have two characters.
• Lists or arrays are often written in the plural form, e.g. coordinates.
• When a variable represents a number of elements of some kind, the prefix n is used, e.g. natom.
• For integer loop variables, use the prefix i, e.g. iatom. (Often a single i and j are still used for this purpose.)

2.9.2. Variable names and prefixes¶

at
Common prefix for a variable related to an atom. (Used when similar variables exist that are not related to atoms, e.g. atgrid.)
coordintes
3D Cartesian coordinates of the nuclei. (Singular form is also used for the coordinate of a single atom.)
dm
A density matrix. (dm_full, dm_spin, dm_alpha, dm_beta for spin-summed, spin difference, alpha and beta density matrices.)
er or electron_repulsion
The electron repulsion two-body operator.
fock
A Fock matrix.
exp
An expansion of orbitals in a basis set, with orbital energies and occupation numbers. (exp_alpha and exp_beta are typically used for alpha and beta orbitals, respectively.)
grid
The specification of an integration grid: the Cartesian coordinates of all the grid points and the corresponding integration weights.
ham
An (effective) hamiltonian.
kin or kinetic
The kinetic energy operator.
lf
A LinalgFactory instance.
mol
A IOData instance.
moldens
The spin-summed electron density (typically as an array of electron density values evaluated on a grid.)
na or nuclear_attraction
The nuclear attraction operator.
numbers
An array with atomic numbers. (Singular form is also used for the atomic number of a single atom.)
log
The screen logger of HORTON (See horton.log.)
obasis
An orbital basis.
occ_model
A model to assign occupation numbers to orbitals.
olp or overlap
The overlap operator.
pseudo_numbers
Effective core charges. (Singular form is also used for the effective core charge of a single atom.)
scf_solver
An algorithm to optimize the orbitals as to minimize the energy of an effective Hamiltonian.
spindens
The alpha - beta electron density (typically as an array of electron density values evaluated on a grid.)
wpart
A partitioning scheme.