| Issue | #Downvotes for this reason | By |
|---|
| accept_sparse | Indicate that func accepts a sparse matrix as input. If validate is False, this has no effect. Otherwise, if accept_sparse is false, sparse matrix inputs will cause an exception to be raised | default: true |
| check_inverse | Whether to check that or ``func`` followed by ``inverse_func`` leads to the original inputs. It can be used for a sanity check, raising a warning when the condition is not fulfilled .. versionadded:: 0.20 | default: true |
| feature_names_out | Determines the list of feature names that will be returned by the `get_feature_names_out` method. If it is 'one-to-one', then the output feature names will be equal to the input feature names. If it is a callable, then it must take two positional arguments: this `FunctionTransformer` (`self`) and an array-like of input feature names (`input_features`). It must return an array-like of output feature names. The `get_feature_names_out` method is only defined if `feature_names_out` is not None See ``get_feature_names_out`` for more details .. versionadded:: 1.1 | default: null |
| func | The callable to use for the transformation. This will be passed the same arguments as transform, with args and kwargs forwarded If func is None, then func will be the identity function | default: {"oml-python:serialized_object": "function", "value": "__main__. |
| inv_kw_args | Dictionary of additional keyword arguments to pass to inverse_func .. versionadded:: 0.18 | default: null |
| inverse_func | The callable to use for the inverse transformation. This will be passed the same arguments as inverse transform, with args and kwargs forwarded. If inverse_func is None, then inverse_func will be the identity function | default: null |
| kw_args | Dictionary of additional keyword arguments to pass to func .. versionadded:: 0.18 | default: null |
| validate | Indicate that the input X array should be checked before calling ``func``. The possibilities are: - If False, there is no input validation - If True, then X will be converted to a 2-dimensional NumPy array or sparse matrix. If the conversion is not possible an exception is raised .. versionchanged:: 0.22 The default of ``validate`` changed from True to False | default: false |