def check_array(array, accept_sparse=None, dtype="numeric", order=None,
                copy=False, force_all_finite=True, ensure_2d=True,
                allow_nd=False, ensure_min_samples=1, ensure_min_features=1):
    """Input validation on an array, list, sparse matrix or similar.

    By default, the input is converted to an at least 2nd numpy array.
    If the dtype of the array is object, attempt converting to float,
    raising on failure.

    Parameters
    ----------
    array : object
        Input object to check / convert.

    accept_sparse : string, list of string or None (default=None)
        String[s] representing allowed sparse matrix formats, such as 'csc',
        'csr', etc.  None means that sparse matrix input will raise an error.
        If the input is sparse but not in the allowed format, it will be
        converted to the first listed format.

    dtype : string, type 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.

    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 (default=True)
        Whether to raise an error on np.inf and np.nan in X.

    ensure_2d : boolean (default=True)
        Whether to make X at least 2d.

    allow_nd : boolean (default=False)
        Whether to allow X.ndim > 2.

    ensure_min_samples : int (default=1)
        Make sure that the array has a minimum number of samples in its first
        axis (rows for a 2D array). Setting to 0 disables this check.

    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 the input data has effectively 2
        dimensions or is originally 1D and ``ensure_2d`` is True. Setting to 0
        disables this check.

    Returns
    -------
    X_converted : object
        The converted and validated X.
    """
    if isinstance(accept_sparse, str):
        accept_sparse = [accept_sparse]

    # store whether originally we wanted numeric dtype
    dtype_numeric = dtype == "numeric"

    if sp.issparse(array):
        if dtype_numeric:
            dtype = None
        array = _ensure_sparse_format(array, accept_sparse, dtype, order,
                                      copy, force_all_finite)
    else:
        if ensure_2d:
            array = np.atleast_2d(array)
        if dtype_numeric:
            if hasattr(array, "dtype") and getattr(array.dtype, "kind", None) == "O":
                # if input is object, convert to float.
                dtype = np.float64
            else:
                dtype = None
        array = np.array(array, dtype=dtype, order=order, copy=copy)
        # make sure we actually converted to numeric:
        if dtype_numeric and array.dtype.kind == "O":
            array = array.astype(np.float64)
        if not allow_nd and array.ndim >= 3:
            raise ValueError("Found array with dim %d. Expected <= 2" %
                             array.ndim)
        if force_all_finite:
            _assert_all_finite(array)

    shape_repr = _shape_repr(array.shape)
    if ensure_min_samples > 0:
        n_samples = _num_samples(array)
        if n_samples < ensure_min_samples:
            raise ValueError("Found array with %d sample(s) (shape=%s) while a"
                             " minimum of %d is required."
                             % (n_samples, shape_repr, ensure_min_samples))

    if ensure_min_features > 0 and array.ndim == 2:
        n_features = array.shape[1]
        if n_features < ensure_min_features:
            raise ValueError("Found array with %d feature(s) (shape=%s) while"
                             " a minimum of %d is required."
                             % (n_features, shape_repr, ensure_min_features))
    return array
Input validation on an array, list, sparse matrix or similar.

    By default, the input is converted to an at least 2nd numpy array.
    If the dtype of the array is object, attempt converting to float,
    raising on failure.

    Parameters
    ----------
    array : object
        Input object to check / convert.

    accept_sparse : string, list of string or None (default=None)
        String[s] representing allowed sparse matrix formats, such as 'csc',
        'csr', etc.  None means that sparse matrix input will raise an error.
        If the input is sparse but not in the allowed format, it will be
        converted to the first listed format.

    dtype : string, type 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.

    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 (default=True)
        Whether to raise an error on np.inf and np.nan in X.

    ensure_2d : boolean (default=True)
        Whether to make X at least 2d.

    allow_nd : boolean (default=False)
        Whether to allow X.ndim > 2.

    ensure_min_samples : int (default=1)
        Make sure that the array has a minimum number of samples in its first
        axis (rows for a 2D array). Setting to 0 disables this check.

    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 the input data has effectively 2
        dimensions or is originally 1D and ``ensure_2d`` is True. Setting to 0
        disables this check.

    Returns
    -------
    X_converted : object
        The converted and validated X.