CHANGELOG.md

@@ -4,6 +4,28 @@
 
 [1]: https://pypi.org/project/bigframes/#history
 
+## [0.20.0](https://github.com/googleapis/python-bigquery-dataframes/compare/v0.19.2...v0.20.0) (2024-01-30)
+
+
+### Features
+
+* Add `DataFrame.peek()` as an efficient alternative to `head()` results preview ([#318](https://github.com/googleapis/python-bigquery-dataframes/issues/318)) ([9c34d83](https://github.com/googleapis/python-bigquery-dataframes/commit/9c34d834e83ca5514bee723ebb9a7ad1ad50e88d))
+* Add ARIMA_EVAULATE options in forecasting models ([#336](https://github.com/googleapis/python-bigquery-dataframes/issues/336)) ([73e997b](https://github.com/googleapis/python-bigquery-dataframes/commit/73e997b3e80f844a8120b52ed2ece8b046cf4ca9))
+* Add Index constructor, repr, copy, get_level_values, to_series ([#334](https://github.com/googleapis/python-bigquery-dataframes/issues/334)) ([e5d054e](https://github.com/googleapis/python-bigquery-dataframes/commit/e5d054e93a05f5c504e8db57b954c07d33e5f5b9))
+* Improve error message for drive based BQ table reads ([#344](https://github.com/googleapis/python-bigquery-dataframes/issues/344)) ([0794788](https://github.com/googleapis/python-bigquery-dataframes/commit/0794788a2d232d795d803cd0c5b3f7d51c562cf1))
+* Update cut to work without labels = False and show intervals as dict ([#335](https://github.com/googleapis/python-bigquery-dataframes/issues/335)) ([4ff53db](https://github.com/googleapis/python-bigquery-dataframes/commit/4ff53db48133b817bec5f123b634690244a610d3))
+
+
+### Bug Fixes
+
+* Chance default connection name in getting_started.ipnyb ([#347](https://github.com/googleapis/python-bigquery-dataframes/issues/347)) ([677f014](https://github.com/googleapis/python-bigquery-dataframes/commit/677f0146acf19def88fddbeb0527a078458948ae))
+* Series iteration correctly returns values instead of index ([#339](https://github.com/googleapis/python-bigquery-dataframes/issues/339)) ([2c6af9b](https://github.com/googleapis/python-bigquery-dataframes/commit/2c6af9ba8b362dae39a6e082cdc816c955c73517))
+
+
+### Documentation
+
+* Add code samples for `Series.{between, cumprod}` ([#353](https://github.com/googleapis/python-bigquery-dataframes/issues/353)) ([09a52fd](https://github.com/googleapis/python-bigquery-dataframes/commit/09a52fda19cde8efa6b20731d5b8e21f50b18a9a))
+
 ## [0.19.2](https://github.com/googleapis/python-bigquery-dataframes/compare/v0.19.1...v0.19.2) (2024-01-22)
 
 

bigframes/core/__init__.py

@@ -106,10 +106,10 @@ def get_column_type(self, key: str) -> bigframes.dtypes.Dtype:
         return self._compile_ordered().get_column_type(key)
 
     def _compile_ordered(self) -> compiling.OrderedIR:
-        return compiling.compile_ordered(self.node)
+        return compiling.compile_ordered_ir(self.node)
 
     def _compile_unordered(self) -> compiling.UnorderedIR:
-        return compiling.compile_unordered(self.node)
+        return compiling.compile_unordered_ir(self.node)
 
     def row_count(self) -> ArrayValue:
         """Get number of rows in ArrayValue as a single-entry ArrayValue."""

bigframes/core/blocks.py

@@ -287,15 +287,14 @@ def reset_index(self, drop: bool = True) -> Block:
             A new Block because dropping index columns can break references
             from Index classes that point to this block.
         """
-        block = self
         new_index_col_id = guid.generate_guid()
         expr = self._expr.promote_offsets(new_index_col_id)
         if drop:
             # Even though the index might be part of the ordering, keep that
             # ordering expression as reset_index shouldn't change the row
             # order.
             expr = expr.drop_columns(self.index_columns)
-            block = Block(
+            return Block(
                 expr,
                 index_columns=[new_index_col_id],
                 column_labels=self.column_labels,
@@ -321,13 +320,12 @@ def reset_index(self, drop: bool = True) -> Block:
                 # See: https://pandas.pydata.org/docs/reference/api/pandas.Index.insert.html
                 column_labels_modified = column_labels_modified.insert(level, label)
 
-            block = Block(
+            return Block(
                 expr,
                 index_columns=[new_index_col_id],
                 column_labels=column_labels_modified,
                 index_labels=[None],
             )
-        return block
 
     def set_index(
         self,
@@ -432,8 +430,18 @@ def to_pandas(
                 downsampling=sampling, ordered=ordered
             )
         )
+        df.set_axis(self.column_labels, axis=1, copy=False)
         return df, query_job
 
+    def try_peek(self, n: int = 20) -> typing.Optional[pd.DataFrame]:
+        if self.expr.node.peekable:
+            iterator, _ = self.session._peek(self.expr, n)
+            df = self._to_dataframe(iterator)
+            self._copy_index_to_pandas(df)
+            return df
+        else:
+            return None
+
     def to_pandas_batches(self):
         """Download results one message at a time."""
         dtypes = dict(zip(self.index_columns, self.index_dtypes))

bigframes/core/compile/__init__.py

@@ -13,11 +13,11 @@
 # limitations under the License.
 
 from bigframes.core.compile.compiled import OrderedIR, UnorderedIR
-from bigframes.core.compile.compiler import compile_ordered, compile_unordered
+from bigframes.core.compile.compiler import compile_ordered_ir, compile_unordered_ir
 
 __all__ = [
-    "compile_ordered",
-    "compile_unordered",
+    "compile_ordered_ir",
+    "compile_unordered_ir",
     "OrderedIR",
     "UnorderedIR",
 ]