Narwhals v1.27.1

Changes

🐞 Bug fixes

• fix: PySpark was raising during collect when it contained no rows and a void dtype column (#2032)
• fix: is_in was raising when used with empty list (#2031)

🛠️ Other improvements

• chore: fix pandas-stubs issues (#2008)
• fix(typing): Resolve all mypy & pyright errors for _arrow (#2007)

Thank you to all our contributors for making this release possible!
@EdAbati, @MarcoGorelli and @dangotbanned

Narwhals v1.27.0

Changes

🚀 Performance improvements

• perf: Avoid evaluating expr twice in mean_horizontal (#2028)
• perf: avoid try/except in _hasattr_static (#2014)
• perf: fast path for pandas-like group by with single expression and avoid resetting index if not necessary (#2010)

✨ Enhancements

• feat: support casting to and from spark-like structs (#1991)
• feat: Add support for series[other_series] (#2013)

🐞 Bug fixes

• fix: adjust duckdb population skewness by correction factor to get sample skewness (#2021)
• fix: sqlframe false positives in compliance checks (#2011)

🛠️ Other improvements

• chore(typing): Upgrade TypeGuard -> TypeIs (#2027)
• refactor: remove Array shape default (#2026)
• refactor: reuse Schema.to_<backend>() in from_numpy (#2024)
• chore(typing): relax from_numpy to use Mapping, Sequence (#2023)
• chore(typing): relax from_dict to use Mapping (#2022)
• tests: Allow to run pytest narwhals --doctest-modules without ibis (#2019)
• ci(typing): use tool.mypy.pretty = true (#2018)
• fix: various typos (#2016)
• ci: update pointblank deps to test downstream in ci (#2015)
• chore(typing): resolve time unit/zone set invariance (#2012)
• test: add test for sum_horizontal with column transformation (#2009)
• chore: simplify when implementation (#2003)
• ci: remove pyspark from Windows CI (#1998)
• chore(typing): add overloads to isinstance_or_issubclass (#1997)
• chore: parse series and ndarrays as expressions (#1994)
• chore(typing): remove unused ignores (#1979)
• fix: use mypy pre-commit in local environment (#1966)
• chore: clean up flatten and extract (#1995)
• chore: determine whether to use compliant_frame.aggregate at narwhals level (#1993)
• chore: Refactor filter (#1992)
• chore: alias named expressions at narwhals level (#1990)
• chore: Expr metadata refactor (#1986)
• chore: use toArrow in PySpark 4.0+ (#1987)
• tests: skip cudf hist tests (#1988)

Thank you to all our contributors for making this release possible!
@DeaMariaLeon, @EdAbati, @FBruzzesi, @MarcoGorelli, @anopsy, @camriddell, @dangotbanned and @raisadz

Narwhals v1.26.0

Changes

• ci: validate tpch query results (#1971)
• ci: add pointblank in downstream test (#1956)
• ci: add Validoopsie to downstream tests (#1973)
• chore(typing): fix _from_compliant_dataframe type ignore (#1969)
• fix(typing): resolve remaining utils.py warnings (#1968)
• test: Add new_streaming (#1898)
• fix(typing): add missing Series._level annotation (#1967)
• ci: fix plotly tests location (#1965)

✨ Enhancements

• feat: Series.hist (#1859)
• feat: catch Polars exceptions, unify exception raising more (#1918)
• feat: improving array casting (#1865)
• feat: add datetime selector (#1822)
• feat: add Schema.to_(arrow|pandas|polars) (#1924)

🐞 Bug fixes

• fix: implement casting to Int128 (#1984)
• fix: fix type __get_item__ (#1958)
• fix(typing): Backport from_native overload fixes to v1 (#1953)
• fix(typing): Backport use IntoDataFrameT in to_native to v1 (#1954)

📖 Documentation

• docs: add Schema.to_(arrow|pandas|polars) (#1980)
• RFC, chore: shrink series module docstrings (#1976)
• chore: shrink functions module docstrings (#1974)
• docs: add docstring guidelines to CONTRIBUTING.md (#1957)

🛠️ Other improvements

• chore: minor series.py fixes, dedupe a little (#1982)
• chore(typing): resolve _arrow.dataframe warnings (#1983)
• chore(typing): add np.ndarray aliases (#1977)
• chore: widen parse_version to accept packages (#1975)
• RFC, chore: shrink series module docstrings (#1976)
• chore: shrink functions module docstrings (#1974)
• chore(typing): fix remaining functions, series warnings (#1970)
• fix: missing __getitem__ type fixes (#1963)
• chore(typing): add guards is_compliant_* (+ friends) (#1955)
• chore: reduce duplication, implement more methods at the Narwhals level rather than at the compliant level, fix CI from Ibis release (#1960)

Thank you to all our contributors for making this release possible!
@EdAbati, @FBruzzesi, @IsaiasGutierrezCruz, @MarcoGorelli, @akmalsoliev, @camriddell, @dangotbanned and @luke396

Narwhals v1.25.2

Changes

✨ Enhancements

• feat: restore support of is_duplicated for pyarrow (#1951)

🐞 Bug fixes

• fix: cuDF to_numpy tests were failing (#1949)
• fix: raise NotImplementedError for DataFramte.is_duplicated for PyArrow when there is more than one column (#1948)
• fix: wrong argument name suggested in from_dict deprecation (#1946)

Thank you to all our contributors for making this release possible!
@FBruzzesi and @MarcoGorelli

Narwhals v1.25.1

Changes

🚀 Performance improvements

• perf: use fastpath in DataFrame.to_numpy for pandas, improve performance for DataFrame.schema for pandas, use fewer values to sniff dtype for pandas objects (#1929)

✨ Enhancements

• enh: Deprecate native_namespace in favour of backend in from_dict (#1931)
• feat: validate duplicate column names in pyarrow and duckdb (#1815)

🐞 Bug fixes

• fix: Always collect Iterator[IntoExpr] in utils.flatten (#1934)

📖 Documentation

• docs: Make DataFrame and LazyFrame docstrings shorter and more concise (#1939)
• chore: fix a couple of typos 🙃 (#1921)

🛠️ Other improvements

• ci: fix plotly downstream test (#1938)
• fix(typing): Use IntoDataFrameT in to_native (#1936)
• fix(typing): Use correct TypeVar/Union pairs in from_native (#1935)
• fix(typing): Ensure LazyFrame has a unique TypeVar (#1930)
• refactor: refactoring following refurb and perflint suggestions (#1925)

Thank you to all our contributors for making this release possible!
@DeaMariaLeon, @FBruzzesi, @IsaiasGutierrezCruz, @MarcoGorelli, @dangotbanned, and @raisadz

Narwhals v1.25.0

Changes

✨ Enhancements

• feat: add LazyFrame.explode for duckdb (#1891)
• feat: add duckdb .str.to_datetime (#1916)
• feat: enable ModuleType and str for backend in .lazy() method (#1914)
• feat: add LazyFrame.unpivot for spark and duckdb (#1890)
• feat: LazyFrame.collect with backend and **kwargs (#1734)
• feat: spark date and datetimedata types, allow for dtype in nw.lit for pyspark (#1913)

📖 Documentation

• docs: Minor rendering fixups, inherit all exceptions from NarwhalsError (#1919)
• docs: shorten docstring examples in narwhals/expr.py (#1915)

🛠️ Other improvements

• chore: simplify duckdb group-by (#1911)

Thank you to all our contributors for making this release possible!
@FBruzzesi, @osoucy , and @MarcoGorelli

Narwhals v1.24.2

Changes

✨ Enhancements

• feat: Add backend argument to lazy (#1895)
• feat: add dtype.is_<x> methods (#1906)
• feat: spark like .list namespace and lazyframe .explode (#1887)

🐞 Bug fixes

• fix: pandas was raising when index name and column names overlapped in groupby (#1908)
• docs: update selectors docstrings (#1905)

📖 Documentation

• docs: improve search in docs (#1909)
• docs: update selectors docstrings (#1905)
• docs(ecosystem.md): add pointblank to Used By section (#1904)
• docs(README.md): add mention of pointblank project (#1903)

Thank you to all our contributors for making this release possible!
@DeaMariaLeon, @FBruzzesi, @MarcoGorelli, @raisadz and @rich-iannone

Narwhals v1.24.1

Changes

• chore: fix pyspark/sqlframe typo (#1884)

✨ Enhancements

• feat: start (silently) adding support for SQLFrame (#1883)
• feat: move robust literal handling for PySpark (#1880)
• feat: add selectors.matches (#1882)
• feat: support more scalar operations for duckdb, Increase width for ipython (#1877)

🛠️ Other improvements

• chore: add "typing :: typed" classifier to pyproject.toml (#1881)
• chore: use positional-only arg in evaluate_into_exprs (#1879)
• chore: remove unused _depth from DuckDBExpr and SparkLikeExpr (#1878)
• chore: refactor name namespaces to lower code duplication (#1876)

Thank you to all our contributors for making this release possible!
@FBruzzesi, @MarcoGorelli and @raisadz

Narwhals v1.24.0

Changes

• docs: fix api completness generation in CI (#1863)

✨ Enhancements

• feat: pyspark and duckdb selectors (#1853)
• feat: completely refactor alias tracking and support nw.all, nw.nth, and selectors across the API (#1866)
• feat: raise if expression changes length in .over() (#1867)
• feat: add DuckDB join_asof (#1860)
• feat: allow any ddof value for duckdb var and std (#1858)
• feat: add DuckDB Struct dtype (#1851)
• feat: add DuckDB list.len method (#1850)
• feat: enforce that group-by aggregations actually aggregate (#1844)
• feat: add mean_horizontal for DuckDB (#1846)

🐞 Bug fixes

• fix: support various reductions in pyspark (#1870)
• fix: address & / | operator errors for PySpark / chore: use F.lit in maybe_evaluate for pyspark, like we do for duckdb (#1872)
• fix: allow any name in expression parsing (#1871)
• fix: nw.selectors.by_dtype(nw.Datetime) was excluding tz-aware for Polars (#1869)
• patch: fix duckdb narwhals_to_native_dtype for Int32 and UInt32 (#1857)
• fix: raise on selectors addition (#1854)
• fix: rename ewm and rolling min_periods to min_samples for polars 1.21 compatibility (#1864)
• fix: address & / | operator errors for PySpark / chore: use F.lit in maybe_evaluate for pyspark, like we do for duckdb (#1872)

🛠️ Other improvements

• test: skip Ibis tests if deps aren't installed, set defaults in PandasLikeSeries.__array__ to fix cuDF is_in (#1862)
• chore: parse strings as columns names at narwhals-level (#1856)
• chore: some typing and default removal (#1852)
• chore: validate expressions shape at narwhals/expr.py level (#1845)
• chore: simplify internal renaming in _pandas_like/series.py (#1847)

Thank you to all our contributors for making this release possible!
@FBruzzesi, @MarcoGorelli and @raisadz

Narwhals v1.23.0

Changes

• ci: downstream test for formulaic (#1817)
• docs: Removed class, added polars to the table, str.head and str.tail are a… (#1801)

✨ Enhancements

• feat: deprecate maintain_order in Expr.unique and LazyFrame.tail (but keep around in stable.v1) (#1839)
• feat: track whether expressions change length but don't aggregate, and only allow length-changing expressions if they're followed by aggregations in the lazy API (#1828)
• feat: add DuckDB: nw.nth, nw.sum_horizontal, nw.concat_str, group_by with drop_null_keys (#1832)
• feat: remove eager_or_interchange from from_native in main namespace, switch Ibis' support from interchange to lazy in main namespace (but preserve status-quo in stable.v1) (#1829)
• feat: add is_nan and is_finite for duckdb, is_nan for pyspark (#1825)
• chore: rename time zone tests (#1830)
• feat: Deprecate Expr.arg_true (but keep Series.arg_true, and keep both available in stable.v1) (#1827)
• feat: add Expr.dt methods to PySpark (#1835)
• feat: add pyspark str namespace to_datetime (#1826)
• feat: add total duration methods for DuckDB (#1831)
• feat: add .over method for SparkLikeExpr (#1808)
• feat: pyspark group by n_unique and no aggregation (#1819)
• feat: Disallow order-dependent expressions from being passed to nw.LazyFrame (#1806)
• feat: add SparkExpr.cast for basic types (#1812)
• feat: pyspark and duckdb Expr.name namespace (#1809)
• feat: add AnonymousExprError (#1816)
• feat: deprecate Expr.head, Expr.tail, Expr.sort, Expr.gather_every, Expr.sample (but keep them in stable.v1) (#1791)
• feat: add duckdb dataframe drop_nulls (#1811)
• feat: add DataFrame and Series to_polars (#1803)
• feat: add support for SparkLikeNamespace.when (#1805)

🐞 Bug fixes

• fix: when/then/otherwise output name was not consistent across backends (#1833)
• fix: raise on shape mismatch in filter (#1814)
• patch: fix when-then double lit case (#1810)

🛠️ Other improvements

• chore: simplify imports (#1838)
• test: fixup test suite for cudf.pandas (#1837)
• test: decouple pyspark constructor from pandas (#1834)
• chore: refactor pandas-like narwhals_to_native_dtype (#1824)
• chore: refactor isinstance_or_issubclass to allow tuples (#1820)

Thank you to all our contributors for making this release possible!
@Dhanunjaya-Elluri, @EdAbati, @FBruzzesi, @MarcoGorelli, @luke396, @marvinl803 and @raisadz