Tags for the input data.
Whether the input can be a 1D array.
Whether the input can be a 2D array. Note that most common tests currently run only if this flag is set to True.
Whether the input can be a 3D array.
Whether the input can be a sparse matrix.
Whether the input can be categorical.
Whether the input can be an array-like of strings.
Whether the input can be a dictionary.
Whether the estimator requires positive X.
Whether the estimator supports data with missing values encoded as np.nan.
This boolean attribute indicates whether the data (X), fit and similar methods consists of pairwise measures over samples rather than a feature representation for each sample. It is usually True where an estimator has a metric or affinity or kernel parameter with value ‘precomputed’. Its primary purpose is to support a meta-estimator or a cross validation procedure that extracts a sub-sample of data intended for a pairwise estimator, where the data needs to be indexed on both axes. Specifically, this tag is used by sklearn.utils.metaestimators._safe_split to slice rows and columns.
Note that if setting this tag to True means the estimator can take only positive values, the positive_only tag must reflect it and also be set to True.
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https://scikit-learn.org/1.6/modules/generated/sklearn.utils.InputTags.html