magnopy.Convention#

class magnopy.Convention(multiple_counting: bool = None, spin_normalized: bool = None, c1: float = None, c21: float = None, c22: float = None, c31: float = None, c32: float = None, c33: float = None, c41: float = None, c42: float = None, c43: float = None, c44: float = None, c45: float = None, name: str = 'custom')[source]#

Convention of the spin Hamiltonian.

For more details see Convention of the Hamiltonian and Spin Hamiltonian.

Parameters:

multiple_countingbool, optional: Whether the pairs of spins are counted multiple times in the Hamiltonian's sums.
spin_normalizedbool, optional: Whether spin vectors/operators are "normalized" to 1. If True, then spin vectors/operators are "normalized".
c1float, optional: Numerical factor before the sum over sites in the spin Hamiltonian (( 1 ) terms).
c21float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((2, 1) terms).
c22float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((2, 2) terms).
c31float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((3, 1) terms).
c32float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((3, 2) terms).
c33float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((3, 3) terms).
c41float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((4, 1) terms).
c42float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((4, 2) terms).
c43float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((4, 3) terms).
c44float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((4, 4) terms).
c45float, optional: Numerical factor before the sum over sites in the spin Hamiltonian ((4, 5) terms).
namestr, default "custom": A label for the convention. Any string, case-insensitive.

Examples

Creating conventions

>>> import magnopy
>>> conv_1 = magnopy.Convention(True, True, c21=1, c22=-0.5, name="conv #1")
>>> conv_2 = magnopy.Convention(False, True, c21=1, c22=-0.5, name="conv #2")
>>> conv_3 = magnopy.Convention(False, True, c22=-0.5, name="conv #3")

Individual properties of the convention

>>> conv_1.multiple_counting
True
>>> conv_3.c21
Traceback (most recent call last):
...
magnopy._exceptions.ConventionError: Convention of spin Hamiltonian has an undefined property 'c21':
"conv #3" convention where
  * Bonds are counted once in the sum;
  * Spin vectors are normalized to 1;
  * Undefined c1 factor;
  * Undefined c21 factor;
  * c22 = -0.5;
  * Undefined c31 factor;
  * Undefined c32 factor;
  * Undefined c33 factor;
  * Undefined c41 factor;
  * Undefined c42 factor;
  * Undefined c43 factor;
  * Undefined c44 factor;
  * Undefined c45 factor.
>>> conv_3.name
'conv #3'

Full summary of the convention

>>> print(conv_1)
"conv #1" convention where
  * Bonds are counted multiple times in the sum;
  * Spin vectors are normalized to 1;
  * Undefined c1 factor;
  * c21 = 1.0;
  * c22 = -0.5;
  * Undefined c31 factor;
  * Undefined c32 factor;
  * Undefined c33 factor;
  * Undefined c41 factor;
  * Undefined c42 factor;
  * Undefined c43 factor;
  * Undefined c44 factor;
  * Undefined c45 factor.

Comparing conventions

>>> conv_1 == conv_2
False
>>> conv_1 != conv_3
True

Methods

`get_modified`([multiple_counting, ...])	Returns a new instance of the `Convention` class.
`get_predefined`(name)	Returns one of the predefined conventions.
`summary`([return_as_string])	Gives human-readable summary of the convention.

Properties

`c1`	Numerical factor before the sum over sites in the spin Hamiltonian (( 1 ) terms).
`c21`	Numerical factor before the sum over sites in the spin Hamiltonian ((2, 1) terms).
`c22`	Numerical factor before the sum over sites in the spin Hamiltonian ((2, 2) terms).
`c31`	Numerical factor before the sum over sites in the spin Hamiltonian ((3, 1) terms).
`c32`	Numerical factor before the sum over sites in the spin Hamiltonian ((3, 2) terms).
`c33`	Numerical factor before the sum over sites in the spin Hamiltonian ((3, 3) terms).
`c41`	Numerical factor before the sum over sites in the spin Hamiltonian ((4, 1) terms).
`c42`	Numerical factor before the sum over sites in the spin Hamiltonian ((4, 2) terms).
`c43`	Numerical factor before the sum over sites in the spin Hamiltonian ((4, 3) terms).
`c44`	Numerical factor before the sum over sites in the spin Hamiltonian ((4, 4) terms).
`c45`	Numerical factor before the sum over sites in the spin Hamiltonian ((4, 5) terms).
`multiple_counting`	Whether the all elements of the equivalent sets of interaction parameters are included in the Hamiltonian's sums.
`name`	A label for the convention.
`spin_normalized`	Whether spin vectors/operators are "normalized" to 1.