CrystalNNFingerprint

class emmet.core.featurization.featurizers.CrystalNNFingerprint(op_types=<factory>, crystalnn=<factory>, _ops=None)

Bases: Featurizer

A local order parameter fingerprint for periodic crystals.

Adapted from matminer.featurizers.site.fingerprint.

The fingerprint represents the value of various order parameters for the site. The “wt” order parameter describes how consistent a site is with a certain coordination number. The remaining order parameters are computed by multiplying the “wt” for that coordination number with the OP value.

Args:

op_types (dict): a dict of coordination number (int) to a list of str

representing the order parameter types

crystalnn (CrystalNN)an instance of CrystalNN to use in identifying

local coordination environments.

Parameters:

• op_types (dict[int, list[str]])

• crystalnn (CrystalNN)

• _ops (dict[int, list[str | LocalStructOrderParams]] | None)

classmethod from_preset(preset, **kwargs)

Use preset parameters to get the fingerprint

Return type:

Self

Parameters:

preset (Literal['cn', 'ops'])

Args:

preset (‘cn’ | ‘ops’): Initializes the featurizer to use coordination number (‘cn’) or structural

order parameters like octahedral, tetrahedral (‘ops’).

**kwargs: other settings to be passed into CrystalNN class

featurize(struct, idx)

Get crystal fingerprint of site with given index in input structure. Args:

struct (Structure): Pymatgen Structure object. idx (int): index of target site in structure.

Returns:

list of weighted order parameters of target site.

Return type:

list[float]

Parameters:

• struct (Structure)

• idx (int)

property feature_labels

Generate feature labels.

Returns:

list of str, the labels of the features