feat: Added Table.transform_table method which returns the transfor…

…med Table (#229)

Closes #110.

### Summary of Changes

Added `Table.transform_table` Method which returns a Table transformed
with the given `TableTransformer`

Co-authored-by: Marsmaennchen221
<[email protected]>

---------

Co-authored-by: megalinter-bot <[email protected]>
Co-authored-by: Alexander Gréus <[email protected]>
Co-authored-by: Lars Reimann <[email protected]>

src/safeds/data/tabular/containers/_table.py

@@ -34,7 +34,7 @@
 if TYPE_CHECKING:
     from collections.abc import Callable, Iterable
 
-    from safeds.data.tabular.transformation import InvertibleTableTransformer
+    from safeds.data.tabular.transformation import InvertibleTableTransformer, TableTransformer
 
     from ._tagged_table import TaggedTable
 
@@ -993,6 +993,40 @@ def transform_column(self, name: str, transformer: Callable[[Row], Any]) -> Tabl
             return self.replace_column(name, result)
         raise UnknownColumnNameError([name])
 
+    def transform_table(self, transformer: TableTransformer) -> Table:
+        """
+        Apply a learned transformation onto this table.
+
+        Parameters
+        ----------
+        transformer : TableTransformer
+            The transformer which transforms the given table.
+
+        Returns
+        -------
+        transformed_table : Table
+            The transformed table.
+
+        Raises
+        ------
+        TransformerNotFittedError
+            If the transformer has not been fitted yet.
+
+        Examples
+        --------
+        >>> from safeds.data.tabular.transformation import OneHotEncoder
+        >>> from safeds.data.tabular.containers import Table
+        >>> transformer = OneHotEncoder()
+        >>> table = Table.from_dict({"col1": [1, 2, 1], "col2": [1, 2, 4]})
+        >>> transformer = transformer.fit(table, None)
+        >>> table.transform_table(transformer)
+           col1_1  col1_2  col2_1  col2_2  col2_4
+        0     1.0     0.0     1.0     0.0     0.0
+        1     0.0     1.0     0.0     1.0     0.0
+        2     1.0     0.0     0.0     0.0     1.0
+        """
+        return transformer.transform(self)
+
     def inverse_transform_table(self, transformer: InvertibleTableTransformer) -> Table:
         """
         Invert the transformation applied by the given transformer.
@@ -1005,7 +1039,7 @@ def inverse_transform_table(self, transformer: InvertibleTableTransformer) -> Ta
         Returns
         -------
         table : Table
-            The original table
+            The original table.
 
         Raises
         ------

tests/safeds/data/tabular/containers/_table/test_inverse_transform_table.py

@@ -4,7 +4,7 @@
 from safeds.data.tabular.transformation import OneHotEncoder
 
 
-class TestInverseTransformTableOnOneHotEncoder:
+class TestInverseTransformTable:
     @pytest.mark.parametrize(
         ("table_to_fit", "column_names", "table_to_transform"),
         [

tests/safeds/data/tabular/containers/_table/test_transform_table.py

@@ -0,0 +1,120 @@
+import pytest
+from safeds.data.tabular.containers import Table
+from safeds.data.tabular.exceptions import TransformerNotFittedError, UnknownColumnNameError
+from safeds.data.tabular.transformation import OneHotEncoder
+
+
+class TestTransform:
+    @pytest.mark.parametrize(
+        ("table", "column_names", "expected"),
+        [
+            (
+                Table.from_dict(
+                    {
+                        "col1": ["a", "b", "b", "c"],
+                    },
+                ),
+                None,
+                Table.from_dict(
+                    {
+                        "col1_a": [1.0, 0.0, 0.0, 0.0],
+                        "col1_b": [0.0, 1.0, 1.0, 0.0],
+                        "col1_c": [0.0, 0.0, 0.0, 1.0],
+                    },
+                ),
+            ),
+            (
+                Table.from_dict(
+                    {
+                        "col1": ["a", "b", "b", "c"],
+                        "col2": ["a", "b", "b", "c"],
+                    },
+                ),
+                ["col1"],
+                Table.from_dict(
+                    {
+                        "col1_a": [1.0, 0.0, 0.0, 0.0],
+                        "col1_b": [0.0, 1.0, 1.0, 0.0],
+                        "col1_c": [0.0, 0.0, 0.0, 1.0],
+                        "col2": ["a", "b", "b", "c"],
+                    },
+                ),
+            ),
+            (
+                Table.from_dict(
+                    {
+                        "col1": ["a", "b", "b", "c"],
+                        "col2": ["a", "b", "b", "c"],
+                    },
+                ),
+                ["col1", "col2"],
+                Table.from_dict(
+                    {
+                        "col1_a": [1.0, 0.0, 0.0, 0.0],
+                        "col1_b": [0.0, 1.0, 1.0, 0.0],
+                        "col1_c": [0.0, 0.0, 0.0, 1.0],
+                        "col2_a": [1.0, 0.0, 0.0, 0.0],
+                        "col2_b": [0.0, 1.0, 1.0, 0.0],
+                        "col2_c": [0.0, 0.0, 0.0, 1.0],
+                    },
+                ),
+            ),
+        ],
+        ids=["all columns", "one column", "multiple columns"],
+    )
+    def test_should_return_transformed_table(
+        self,
+        table: Table,
+        column_names: list[str] | None,
+        expected: Table,
+    ) -> None:
+        transformer = OneHotEncoder().fit(table, column_names)
+        assert table.transform_table(transformer) == expected
+
+    def test_should_not_change_original_table(self) -> None:
+        table = Table.from_dict(
+            {
+                "col1": ["a", "b", "c"],
+            },
+        )
+
+        transformer = OneHotEncoder().fit(table, None)
+        table.transform_table(transformer)
+
+        expected = Table.from_dict(
+            {
+                "col1": ["a", "b", "c"],
+            },
+        )
+
+        assert table == expected
+
+    def test_should_raise_if_column_not_found(self) -> None:
+        table_to_fit = Table.from_dict(
+            {
+                "col1": ["a", "b", "c"],
+            },
+        )
+
+        transformer = OneHotEncoder().fit(table_to_fit, None)
+
+        table_to_transform = Table.from_dict(
+            {
+                "col2": ["a", "b", "c"],
+            },
+        )
+
+        with pytest.raises(UnknownColumnNameError):
+            table_to_transform.transform_table(transformer)
+
+    def test_should_raise_if_not_fitted(self) -> None:
+        table = Table.from_dict(
+            {
+                "col1": ["a", "b", "c"],
+            },
+        )
+
+        transformer = OneHotEncoder()
+
+        with pytest.raises(TransformerNotFittedError):
+            table.transform_table(transformer)