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snowflake.ml.modeling.cluster.OPTICSΒΆ

class snowflake.ml.modeling.cluster.OPTICS(*, min_samples=5, max_eps=inf, metric='minkowski', p=2, metric_params=None, cluster_method='xi', eps=None, xi=0.05, predecessor_correction=True, min_cluster_size=None, algorithm='auto', leaf_size=30, memory=None, n_jobs=None, input_cols: Optional[Union[str, Iterable[str]]] = None, output_cols: Optional[Union[str, Iterable[str]]] = None, label_cols: Optional[Union[str, Iterable[str]]] = None, drop_input_cols: Optional[bool] = False, sample_weight_col: Optional[str] = None)ΒΆ

Bases: BaseTransformer

Estimate clustering structure from vector array For more details on this class, see sklearn.cluster.OPTICS

min_samples: int > 1 or float between 0 and 1, default=5

The number of samples in a neighborhood for a point to be considered as a core point. Also, up and down steep regions can’t have more than min_samples consecutive non-steep points. Expressed as an absolute number or a fraction of the number of samples (rounded to be at least 2).

max_eps: float, default=np.inf

The maximum distance between two samples for one to be considered as in the neighborhood of the other. Default value of np.inf will identify clusters across all scales; reducing max_eps will result in shorter run times.

metric: str or callable, default=’minkowski’

Metric to use for distance computation. Any metric from scikit-learn or scipy.spatial.distance can be used.

If metric is a callable function, it is called on each pair of instances (rows) and the resulting value recorded. The callable should take two arrays as input and return one value indicating the distance between them. This works for Scipy’s metrics, but is less efficient than passing the metric name as a string. If metric is β€œprecomputed”, X is assumed to be a distance matrix and must be square.

Valid values for metric are:

  • from scikit-learn: [β€˜cityblock’, β€˜cosine’, β€˜euclidean’, β€˜l1’, β€˜l2’, β€˜manhattan’]

  • from scipy.spatial.distance: [β€˜braycurtis’, β€˜canberra’, β€˜chebyshev’, β€˜correlation’, β€˜dice’, β€˜hamming’, β€˜jaccard’, β€˜kulsinski’, β€˜mahalanobis’, β€˜minkowski’, β€˜rogerstanimoto’, β€˜russellrao’, β€˜seuclidean’, β€˜sokalmichener’, β€˜sokalsneath’, β€˜sqeuclidean’, β€˜yule’]

Sparse matrices are only supported by scikit-learn metrics. See the documentation for scipy.spatial.distance for details on these metrics.

p: float, default=2

Parameter for the Minkowski metric from pairwise_distances. When p = 1, this is equivalent to using manhattan_distance (l1), and euclidean_distance (l2) for p = 2. For arbitrary p, minkowski_distance (l_p) is used.

metric_params: dict, default=None

Additional keyword arguments for the metric function.

cluster_method: str, default=’xi’

The extraction method used to extract clusters using the calculated reachability and ordering. Possible values are β€œxi” and β€œdbscan”.

eps: float, default=None

The maximum distance between two samples for one to be considered as in the neighborhood of the other. By default it assumes the same value as max_eps. Used only when cluster_method='dbscan'.

xi: float between 0 and 1, default=0.05

Determines the minimum steepness on the reachability plot that constitutes a cluster boundary. For example, an upwards point in the reachability plot is defined by the ratio from one point to its successor being at most 1-xi. Used only when cluster_method='xi'.

predecessor_correction: bool, default=True

Correct clusters according to the predecessors calculated by OPTICS [2]_. This parameter has minimal effect on most datasets. Used only when cluster_method='xi'.

min_cluster_size: int > 1 or float between 0 and 1, default=None

Minimum number of samples in an OPTICS cluster, expressed as an absolute number or a fraction of the number of samples (rounded to be at least 2). If None, the value of min_samples is used instead. Used only when cluster_method='xi'.

algorithm: {β€˜auto’, β€˜ball_tree’, β€˜kd_tree’, β€˜brute’}, default=’auto’

Algorithm used to compute the nearest neighbors:

  • β€˜ball_tree’ will use BallTree.

  • β€˜kd_tree’ will use KDTree.

  • β€˜brute’ will use a brute-force search.

  • β€˜auto’ (default) will attempt to decide the most appropriate algorithm based on the values passed to fit() method.

Note: fitting on sparse input will override the setting of this parameter, using brute force.

leaf_size: int, default=30

Leaf size passed to BallTree or KDTree. This can affect the speed of the construction and query, as well as the memory required to store the tree. The optimal value depends on the nature of the problem.

memory: str or object with the joblib.Memory interface, default=None

Used to cache the output of the computation of the tree. By default, no caching is done. If a string is given, it is the path to the caching directory.

n_jobs: int, default=None

The number of parallel jobs to run for neighbors search. None means 1 unless in a joblib.parallel_backend context. -1 means using all processors. See Glossary for more details.

input_cols: Optional[Union[str, List[str]]]

A string or list of strings representing column names that contain features. If this parameter is not specified, all columns in the input DataFrame except the columns specified by label_cols and sample-weight_col parameters are considered input columns.

label_cols: Optional[Union[str, List[str]]]

A string or list of strings representing column names that contain labels. This is a required param for estimators, as there is no way to infer these columns. If this parameter is not specified, then object is fitted without labels(Like a transformer).

output_cols: Optional[Union[str, List[str]]]

A string or list of strings representing column names that will store the output of predict and transform operations. The length of output_cols mus match the expected number of output columns from the specific estimator or transformer class used. If this parameter is not specified, output column names are derived by adding an OUTPUT_ prefix to the label column names. These inferred output column names work for estimator’s predict() method, but output_cols must be set explicitly for transformers.

sample_weight_col: Optional[str]

A string representing the column name containing the examples’ weights. This argument is only required when working with weighted datasets.

drop_input_cols: Optional[bool], default=False

If set, the response of predict(), transform() methods will not contain input columns.

Methods

fit(dataset)

Perform OPTICS clustering For more details on this function, see sklearn.cluster.OPTICS.fit

score(dataset)

Method not supported for this class.

set_input_cols(input_cols)

Input columns setter.

to_sklearn()

Get sklearn.cluster.OPTICS object.

Attributes

model_signatures

Returns model signature of current class.