# Cluster expansions¶

class icet.ClusterExpansion(cluster_space, parameters)[source]

Cluster expansion model

cluster_space

cluster space that was used for constructing the cluster expansion

Type: icet.ClusterSpace
parameters

effective cluster interactions (ECIs)

Type: numpy.ndarray
cluster_space

cluster space on which cluster expansion is based

Return type: ClusterSpace
orders
Return type: List[~T]
parameters

effective cluster interactions (ECIs)

Return type: List[float]
parameters_as_dataframe

dataframe containing orbit data and ECIs

Return type: DataFrame
predict(structure)[source]

Predicts the property of interest (e.g., the energy) for the input structure using the cluster expansion.

Parameters: structure (Union[Atoms, Structure]) – atomic configuration property value of predicted by the cluster expansion float
prune(indices=None, tol=0)[source]

Removes orbits from the cluster expansion (CE), for which the effective cluster interactions (ECIs; parameters) are zero or close to zero. This commonly reduces the computational cost for evaluating the CE and is therefore recommended prior to using it in production. If the method is called without arguments orbits will be pruned, for which the ECIs are strictly zero. Less restrictive pruning can be achived by setting the tol keyword.

Parameters: indices (Optional[List[int]]) – indices to parameters to remove in the cluster expansion. tol (float) – orbits for which the absolute ECIs is/are within this value will be pruned
static read(filename)[source]

Parameters: filename (str) – file from which to read
write(filename)[source]
Parameters: filename (str) – name of file to which to write