SimpleImputer
Bases: TableTransformer
Replace missing values using the given strategy.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
strategy |
Strategy
|
How to replace missing values. |
required |
value_to_replace |
float | str | None
|
The value that should be replaced. |
None
|
column_names |
str | list[str] | None
|
The list of columns used to fit the transformer. If |
None
|
Examples:
>>> from safeds.data.tabular.containers import Column, Table
>>> from safeds.data.tabular.transformation import SimpleImputer
>>>
>>> table = Table.from_columns(
... [
... Column("a", [1, 3, None]),
... Column("b", [None, 2, 3]),
... ],
... )
>>> transformer = SimpleImputer(SimpleImputer.Strategy.constant(0))
>>> transformed_table = transformer.fit_and_transform(table)
Source code in src/safeds/data/tabular/transformation/_simple_imputer.py
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|
is_fitted: bool
¶
Whether the transformer is fitted.
strategy: SimpleImputer.Strategy
¶
The strategy used to replace missing values.
value_to_replace: Any
¶
The value that should be replaced.
Strategy
¶
Bases: ABC
Various strategies to replace missing values.
Use the static factory methods to create instances of this class.
Source code in src/safeds/data/tabular/transformation/_simple_imputer.py
fit
¶
Learn a transformation for a set of columns in a table.
This transformer is not modified.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
table |
Table
|
The table used to fit the transformer. |
required |
Returns:
Name | Type | Description |
---|---|---|
fitted_transformer |
SimpleImputer
|
The fitted transformer. |
Raises:
Type | Description |
---|---|
ColumnNotFoundError
|
If column_names contain a column name that is missing in the table |
ValueError
|
If the table contains 0 rows |
NonNumericColumnError
|
If the strategy is set to either Mean or Median and the specified columns of the table contain non-numerical data. |
Source code in src/safeds/data/tabular/transformation/_simple_imputer.py
fit_and_transform
¶
Learn a transformation for a set of columns in a table and apply the learned transformation to the same table.
Note: Neither this transformer nor the given table are modified.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
table |
Table
|
The table used to fit the transformer. The transformer is then applied to this table. |
required |
Returns:
Name | Type | Description |
---|---|---|
fitted_transformer |
Self
|
The fitted transformer. |
transformed_table |
Table
|
The transformed table. |
Source code in src/safeds/data/tabular/transformation/_table_transformer.py
transform
¶
Apply the learned transformation to a table.
The table is not modified.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
table |
Table
|
The table to which the learned transformation is applied. |
required |
Returns:
Name | Type | Description |
---|---|---|
transformed_table |
Table
|
The transformed table. |
Raises:
Type | Description |
---|---|
TransformerNotFittedError
|
If the transformer has not been fitted yet. |
ColumnNotFoundError
|
If the input table does not contain all columns used to fit the transformer. |