from functools import wraps
import numpy as np
import pandas as pd
from woodwork.exceptions import WoodworkNotInitError
from woodwork.utils import _get_column_logical_type, import_or_none
dd = import_or_none("dask.dataframe")
ps = import_or_none("pyspark.pandas")
[docs]def init_series(
series,
logical_type=None,
semantic_tags=None,
use_standard_tags=True,
description=None,
origin=None,
metadata=None,
):
"""Initializes Woodwork typing information for a series, numpy.ndarray or pd.api.extensions.
ExtensionArray, returning a new Series. The dtype of the returned series will be converted
to match the dtype associated with the LogicalType.
Args:
series (pd.Series, dd.Series, ps.Series, numpy.ndarray or pd.api.extensions.ExtensionArray):
The original series from which to create the Woodwork initialized series.
logical_type (LogicalType or str, optional): The logical type that should be assigned
to the series. If no value is provided, the LogicalType for the series will
be inferred.
semantic_tags (str or list or set, optional): Semantic tags to assign to the series.
Defaults to an empty set if not specified. There are two options for
specifying the semantic tags:
(str) If only one semantic tag is being set, a single string can be passed.
(list or set) If multiple tags are being set, a list or set of strings can be passed.
use_standard_tags (bool, optional): If True, will add standard semantic tags to the series
based on the inferred or specified logical type of the series. Defaults to True.
description (str, optional): Optional text describing the contents of the series.
origin (str, optional): Optional text specifying origin of the column (i.e. "base" or "engineered").
metadata (dict[str -> json serializable], optional): Metadata associated with the series.
Returns:
Series: A series with Woodwork typing information initialized
"""
if not _is_series(series):
if (
isinstance(series, (np.ndarray, pd.api.extensions.ExtensionArray))
and series.ndim == 1
):
series = pd.Series(series)
elif isinstance(series, np.ndarray) and series.ndim != 1:
raise ValueError(
f"np.ndarray input must be 1 dimensional. Current np.ndarray is {series.ndim} dimensional"
)
else:
raise TypeError(
f"Input must be of series type. The current input is of type {type(series)}"
)
logical_type = _get_column_logical_type(series, logical_type, series.name)
new_series = logical_type.transform(series)
new_series.ww.init(
logical_type=logical_type,
semantic_tags=semantic_tags,
use_standard_tags=use_standard_tags,
description=description,
origin=origin,
metadata=metadata,
)
return new_series
def _is_series(data):
if isinstance(data, pd.Series):
return True
elif _is_dask_series(data):
return True
elif _is_spark_series(data):
return True
return False
def _is_dataframe(data):
if isinstance(data, pd.DataFrame):
return True
elif _is_dask_dataframe(data):
return True
elif _is_spark_dataframe(data):
return True
return False
[docs]def get_invalid_schema_message(dataframe, schema):
"""Return a message indicating the reason that the provided schema cannot be used to
initialize Woodwork on the dataframe. If the schema is valid for the dataframe,
None will be returned.
Args:
dataframe (DataFrame): The dataframe against which to check the schema.
schema (ww.TableSchema): The schema to use in the validity check.
Returns:
str or None: The reason that the schema is invalid for the dataframe
"""
dataframe_cols = set(dataframe.columns)
schema_cols = set(schema.columns.keys())
df_cols_not_in_schema = dataframe_cols - schema_cols
if df_cols_not_in_schema:
return (
f"The following columns in the DataFrame were missing from the typing information: "
f"{df_cols_not_in_schema}"
)
schema_cols_not_in_df = schema_cols - dataframe_cols
if schema_cols_not_in_df:
return (
f"The following columns in the typing information were missing from the DataFrame: "
f"{schema_cols_not_in_df}"
)
logical_types = schema.logical_types
for name in dataframe.columns:
df_dtype = dataframe[name].dtype
valid_dtype = logical_types[name]._get_valid_dtype(type(dataframe[name]))
if str(df_dtype) != valid_dtype:
return (
f"dtype mismatch for column {name} between DataFrame dtype, "
f"{df_dtype}, and {logical_types[name]} dtype, {valid_dtype}"
)
if schema.index is not None and isinstance(dataframe, pd.DataFrame):
# Index validation not performed for Dask/Spark
if not pd.Series(dataframe.index, dtype=dataframe[schema.index].dtype).equals(
pd.Series(dataframe[schema.index].values)
):
return "Index mismatch between DataFrame and typing information"
elif not dataframe[schema.index].is_unique:
return "Index column is not unique"
elif dataframe[schema.index].isnull().any():
return "Index contains null values"
[docs]def is_schema_valid(dataframe, schema):
"""Check if a schema is valid for initializing Woodwork on a dataframe
Args:
dataframe (DataFrame): The dataframe against which to check the schema.
schema (ww.TableSchema): The schema to use in the validity check.
Returns:
boolean: Boolean indicating whether the schema is valid for the dataframe
"""
invalid_schema_message = get_invalid_schema_message(dataframe, schema)
if invalid_schema_message:
return False
return True
def _is_dask_series(data):
if dd and isinstance(data, dd.Series):
return True
return False
def _is_dask_dataframe(data):
if dd and isinstance(data, dd.DataFrame):
return True
return False
def _is_spark_dataframe(data):
if ps and isinstance(data, ps.DataFrame):
return True
return False
def _is_spark_series(data):
if ps and isinstance(data, ps.Series):
return True
return False
def _check_column_schema(method):
"""Decorator for WoodworkColumnAccessor that checks schema initialization"""
@wraps(method)
def wrapper(self, *args, **kwargs):
if self._schema is None:
msg = (
"Woodwork not initialized for this Series. Initialize by "
"calling Series.ww.init"
)
raise WoodworkNotInitError(msg)
return method(self, *args, **kwargs)
return wrapper
def _check_table_schema(method):
"""Decorator for WoodworkTableAccessor that checks schema initialization"""
@wraps(method)
def wrapper(self, *args, **kwargs):
if self._schema is None:
msg = (
"Woodwork not initialized for this DataFrame. Initialize by "
"calling DataFrame.ww.init"
)
raise WoodworkNotInitError(msg)
return method(self, *args, **kwargs)
return wrapper