Input validation for standard estimators.
Checks X and y for consistent length, enforces X to be 2D and y 1D. By
default, X is checked to be non-empty and containing only finite values.
Standard input checks are also applied to y, such as checking that y
does not have np.nan or np.inf targets. For multi-label y, set
multi_output=True to allow 2D and sparse y. If the dtype of X is
object, attempt converting to float, raising on failure.
X (tensor, list or sparse tensor) – Input data.
y (tensor, list or sparse tensor) – Labels.
accept_sparse (string, boolean or list of string (default=False)) – String[s] representing allowed sparse matrix formats, such as ‘csc’,
‘csr’, etc. If the input is sparse but not in the allowed format,
it will be converted to the first listed format. True allows the input
to be any format. False means that a sparse matrix input will
raise an error.
accept_large_sparse (bool (default=True)) – If a CSR, CSC, COO or BSR sparse matrix is supplied and accepted by
accept_sparse, accept_large_sparse will cause it to be accepted only
if its indices are stored with a 32-bit dtype.
dtype (string, type, list of types or None (default="numeric")) – Data type of result. If None, the dtype of the input is preserved.
If “numeric”, dtype is preserved unless array.dtype is object.
If dtype is a list of types, conversion on the first type is only
performed if the dtype of the input is not in the list.
order ('F', 'C' or None (default=None)) – Whether an array will be forced to be fortran or c-style.
copy (boolean (default=False)) – Whether a forced copy will be triggered. If copy=False, a copy might
be triggered by a conversion.
force_all_finite (boolean or 'allow-nan', (default=True)) –
Whether to raise an error on np.inf and np.nan in X. This parameter
does not influence whether y can have np.inf or np.nan values.
The possibilities are:
True: Force all values of X to be finite.
False: accept both np.inf and np.nan in X.
’allow-nan’: accept only np.nan values in X. Values cannot be
ensure_2d (boolean (default=True)) – Whether to raise a value error if X is not 2D.
allow_nd (boolean (default=False)) – Whether to allow X.ndim > 2.
multi_output (boolean (default=False)) – Whether to allow 2D y (array or sparse matrix). If false, y will be
validated as a vector. y cannot have np.nan or np.inf values if
ensure_min_samples (int (default=1)) – Make sure that X has a minimum number of samples in its first
axis (rows for a 2D array).
ensure_min_features (int (default=1)) – Make sure that the 2D array has some minimum number of features
(columns). The default value of 1 rejects empty datasets.
This check is only enforced when X has effectively 2 dimensions or
is originally 1D and ensure_2d is True. Setting to 0 disables
y_numeric (boolean (default=False)) – Whether to ensure that y has a numeric type. If dtype of y is object,
it is converted to float64. Should only be used for regression
estimator (str or estimator instance (default=None)) – If passed, include the name of the estimator in warning messages.
X_converted (object) – The converted and validated X.
y_converted (object) – The converted and validated y.