gators.feature_generation.ElementaryArithmetics¶

class gators.feature_generation.ElementaryArithmetics(columns_a: List[str], columns_b: List[str], operator: str, column_names: List[str] = None, coef: float = 1.0)[source]¶

Create new columns based on elementary arithmetics.

The data should be composed of numerical columns only. Use gators.encoders to replace the categorical columns by numerical ones before using ElementaryArithmetics.

Parameters

columns_aList[str]

List of columns.

columns_bList[str]

List of columns.

operatorstr

Arithmetic perator. The possible values are:

‘+’ for addition
‘*’ for multiplication
‘/’ for division

column_namesList[str], default None.

List of new column names.

coeffloat, default 1.

Coefficient value for the addition.

X[new] = X[column_a] + coef * X[column_b]

dtypetype, default np.float64.

Numerical datatype of the output data.

Examples

Imports and initialization:

>>> from gators.feature_generation import ClusterStatistics
>>> obj = ElementaryArithmetics(
... columns_a=['A'], columns_b=['B'], operator='+', coef=0.1)

The fit, transform, and fit_transform methods accept:

dask dataframes:

>>> import dask.dataframe as dd
>>> import pandas as pd
>>> X = dd.from_pandas(pd.DataFrame({'A': [1, 1., 1.], 'B': [1., 2., 3.]}), npartitions=1)

koalas dataframes:

>>> import databricks.koalas as ks
>>> X = ks.DataFrame({'A': [1, 1., 1.], 'B': [1., 2., 3.]})

and pandas dataframes:

>>> import pandas as pd
>>> X = pd.DataFrame({'A': [1, 1., 1.], 'B': [1., 2., 3.]})

The result is a transformed dataframe belonging to the same dataframe library.

>>> obj.fit_transform(X)
     A    B  A+0.1xB
0  1.0  1.0      1.1
1  1.0  2.0      1.2
2  1.0  3.0      1.3

>>> X = pd.DataFrame({'A': [1, 1., 1.], 'B': [1., 2., 3.]})
>>> _ = obj.fit(X)
>>> obj.transform_numpy(X.to_numpy())
array([[1. , 1. , 1.1],
       [1. , 2. , 1.2],
       [1. , 3. , 1.3]])

fit(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame], y: Union[pd.Series, ks.Series, dd.Series] = None) → gators.feature_generation.elementary_arithmethics.ElementaryArithmetics[source]¶

Fit the transformer on the dataframe X.

Parameters

XDataFrame.: Input dataframe.
ySeries, default None.: Target values.

Returns

ElementaryArithmetics: Instance of itself.

transform(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame]) → Union[pd.DataFrame, ks.DataFrame, dd.DataFrame][source]¶

Transform the dataframe X.

Parameters

XDataFrame.: Input dataframe.

Returns

XDataFrame: Transformed dataframe.

transform_numpy(X: numpy.ndarray) → numpy.ndarray[source]¶

Transform the array X.

Parameters

Xnp.ndarray: Input array.

Returns

Xnp.ndarray: Transformed array.

static get_idx_columns(columns: List[str], selected_columns: List[str]) → numpy.ndarray[source]¶

Get the indices of the columns used for the combination.

Parameters

theta_vecList[float]: List of columns.
selected_theta_vecList[float]: List of columns.
Returns:
np.ndarray: Array of indices.

static check_array(X: numpy.ndarray)¶

Validate array.

Parameters

Xnp.ndarray: Array.

check_array_is_numerics(X: numpy.ndarray)¶

Check if array is only numerics.

Parameters

Xnp.ndarray: Array.

static check_binary_target(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame], y: Union[pd.Series, ks.Series, dd.Series])¶

Raise an error if the target is not binary.

Parameters

ySeries: Target values.

static check_dataframe(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame])¶

Validate dataframe.

Parameters

XDataFrame: Dataframe.

static check_dataframe_contains_numerics(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame])¶

Check if dataframe is only numerics.

Parameters

XDataFrame: Dataframe.

static check_dataframe_is_numerics(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame])¶

Check if dataframe is only numerics.

Parameters

XDataFrame: Dataframe.

check_dataframe_with_objects(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame])¶

Check if dataframe contains object columns.

Parameters

XDataFrame: Dataframe.

check_datatype(dtype, accepted_dtypes)¶

Check if dataframe is only numerics.

Parameters

XDataFrame: Dataframe.

static check_multiclass_target(y: Union[pd.Series, ks.Series, dd.Series])¶

Raise an error if the target is not discrete.

Parameters

ySeries: Target values.

check_nans(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame], columns: List[str])¶

Raise an error if X contains NaN values.

Parameters

XDataFrame: Dataframe.
theta_vecList[float]: List of columns.

static check_regression_target(y: Union[pd.Series, ks.Series, dd.Series])¶

Raise an error if the target is not discrete.

Parameters

ySeries: Target values.

static check_target(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame], y: Union[pd.Series, ks.Series, dd.Series])¶

Validate target.

Parameters

XDataFrame: Dataframe.
ySeries: Target values.

fit_transform(X: Union[pd.DataFrame, ks.DataFrame, dd.DataFrame], y: Union[pd.Series, ks.Series, dd.Series] = None) → Union[pd.DataFrame, ks.DataFrame, dd.DataFrame]¶

Fit and Transform the dataframe X.

Parameters

XDataFrame.: Input dataframe.
ySeries, default None.: Input target.

Returns

XDataFrame: Transformed dataframe.

static get_column_names(inplace: bool, columns: List[str], suffix: str)¶

Return the names of the modified columns.

Parameters

inplacebool: If True return columns. If False return columns__suffix.
columnsList[str]: List of columns.
suffixstr: Suffix used if inplace is False.

Returns

List[str]: List of column names.

get_params(deep=True)¶

Get parameters for this estimator.

Parameters

deepbool, default=True: If True, will return the parameters for this estimator and contained subobjects that are estimators.

Returns

paramsdict: Parameter names mapped to their values.

set_params(**params)¶

Set the parameters of this estimator.

The method works on simple estimators as well as on nested objects (such as Pipeline). The latter have parameters of the form <component>__<parameter> so that it’s possible to update each component of a nested object.

Parameters

**paramsdict: Estimator parameters.

Returns

selfestimator instance: Estimator instance.

gators.feature_generation.ClusterStatistics

gators.feature_generation.PlanRotation