pola-rs/polars rs-0.44.0

Rust Polars 0.44.0

on GitHub

💥 Breaking changes

• Purge arrow-rs support (#19312)

🚀 Performance improvements

• Address inadvertent quadratic behaviour in expand_columns (#19469)
• Move rolling_corr/cov to an actual implementation on Series (#19466)
• Don't split par if cast to categorical (#19462)
• Improve var/cov/corr performance (#19381)
• Reduce memcopy in parquet (#19350)
• Optimize array and list gather (#19327)
• Add/fix unordered row decode, change unordered format (#19284)
• Fast decision for Parquet dictionary encoding (#19256)
• Make date_range / datetime_range ~10x faster for constant durations (#19216)
• Batch utf8-validation in csv 18% / 25% on 1.9.0 (#19124)
• Use two-pass algorithm for csv to ensure correctness and SIMDize more ~17% (#19088)
• Use List's TotalEqKernel (#18984)
• Improve rename performace for Lazy API (#18890)
• Collapse cross-joins to faster joins (#18633)
• Cache register plugin function (#18860)

✨ Enhancements

• Implement nested Parquet writing for High-Precision Decimals (#19476)
• Improve read_database typing (#19444)
• Add IPC sink in new streaming engine (#19431)
• Added escape_regex operation to the str namespace and as a global function (#19257)
• Add SQL support for bit_count and bitwise &, |, and xor operators (#19114)
• Add credential provider utility classes for AWS, GCP (#19297)
• Support decoding Float16 in Parquet (#19278)
• Experimental credential_provider argument for scan_parquet (#19271)
• Allow DeltaTable input to scan_delta and read_delta (#19229)
• Make FlightConsumer Send and support compressed data (#19262)
• New quantile interpolation method & QUANTILE_DISC function in SQL (#19139)
• Conserve Parquet SortingColumns for ints (#19251)
• Low level flight interface (#19239)
• Improved list arithmetic support (#19162)
• Expose LTS CPU in show_versions() (#19193)
• Check Python version when deserializing UDFs (#19175)
• Quantile function in SQL (#18047)
• Improve scalar strict message (#19117)
• Add Series::{first, last, approx_n_unique} (#19093)
• Allow for rolling_*_by to use index count as window (#19071)
• Delay deserialization of python function until physical plan (#19069)
• Add cum(_min/_max) for pl.Boolean (#19061)
• Bitwise operations / aggregations (#18994)
• Improved error message DSL -> IR resolving (#19032)
• Add strict param to eager/lazy frame "rename" (#19017)
• Support schema arg in read/scan_parquet() (#19013)
• Add allow_missing_columns option to read/scan_parquet (#18922)
• Use FFI to extract Series from different Polars binaries (#18964)
• Allow for zero-width fixed size lists (#18940)
• Improve scalar strict message (#18904)
• Support arithmetic between Series with dtype list (#17823)
• Relaxed schema alignment for parquet file list read (#18803)
• Always preserve sorted flag for .dt.date (#18692)
• Implement single inequality joins for join_where (#18727)

🐞 Bug fixes

• Include Array in to_physical (#19474)
• Don't panic in SQL temporal string check; raise suitable ColumnNotFound error (#19473)
• Properly raise on mean_horizontal with wrong dtypes (#19472)
• Make output dtype known for list.to_struct when fields are passed (#19439)
• Address inadvertent quadratic behaviour in expand_columns (#19469)
• Ensure sorted flag is unset after Int->String cast (#19470)
• Fix row_index of batched reader (#19465)
• Fix perfect groupby (#19461)
• Correct wildcard expansion for functions (#19449)
• Ensure struct eq/ne_missing also compares outer validity (#19443)
• Fix incorrect reverse on struct containing NULLs (#19446)
• Faulty escape_regex example (#19440)
• Capture groups should be ignored in replace when literal=True (#19413)
• Fix ColumnNotFound when using pl.element() inside list.eval (#19438)
• Updates error message in csv parser to recommend schema_overrides instead of deprecated dtypes argument (#19416)
• Incorrect .join(..., how="left").head(N) if N <= left_df.height() and there are duplicate matches (#19422)
• Support Array type in more DataType methods (#19427)
• Bug in group_tuples_perfect, tail was not processed properly (#19417)
• Ensure that ASCII* table formats do not use the UTF8 ellipsis char when truncating rows/cols/values (#19404)
• Allow .get(null) in groupby context (#19401)
• Fix include_file_paths and with_row_index for streaming CSV scan (#19394)
• Flaky parametric parquet test (#19393)
• Raise on data mismatch in str.json_decode (#19347)
• Fix unsoundness in group_tuples_perfect (#19359)
• Ensure Python version matches version used to serialize credential provider (#19375)
• Capture groups should be ignored in replace_all when literal=True (#19366)
• Ignore Parquet is_{min,max}_value_exact when set to true (#19344)
• Projection pushdown was ignored by include_file_paths (#19341)
• Don't produce duplicate column names in Series.to_dummies (#19326)
• Use of HAVING outside of GROUP BY should raise a suitable SQLSyntaxError (#19320)
• Fix empty array gather (#19316)
• Merge categorical rev-map in unpivot (#19313)
• DataFrame descending sorting by single list element (#19233)
• Fix cse union schema (#19305)
• Correctly load Parquet statistics for f16 (#19296)
• Error on invalid query (#19303)
• Fix enum scalar output (#19301)
• Fix list gather invalid fast path (#19299)
• Fix quoting style of decimal csv output (#19298)
• Don't vertically parallelize literal select (#19295)
• Fix struct reshape fast path (#19294)
• Also split on forward slashes during hive path inference on Windows (#19282)
• Don't cse as_struct (#19280)
• Only apply string parsing to String dtype (#19222)
• Compilation error missing use JsonLineReader (#19244)
• Don't remember Parquet statistics if filtered (#19248)
• Do not check dtypes of non-projected columns for parquet (#19254)
• Parquet predicate pushdown for lit(_) != (#19246)
• Use all chunks in Series from arrow struct (#19218)
• Implement is_nested_null for Null Array (#19219)
• Fix struct literals (#19214)
• Plotting was not interacting well with Altair schema wrappers (#19213)
• Fixing infer_schema for DataType::Null (#19201)
• Migrate to PyO3 0.22 and released verion of rust-numpy crate (#19199)
• Don't unwrap() expansion (#19196)
• Properly handle non-nullable nested Parquet (#19192)
• Fix invalid list collection in expression engine (#19191)
• Implement to_arrow functionality properly for Arrays (#19077)
• Fix incorrect (eq|ne)_missing on List/Array types (#19155)
• Properly broadcast Struct when then validity (#19148)
• Allow partial name overlap in join_where resolution (#19128)
• Fix floordiv / modulo with scalar 0 on LHS (#19143)
• Ensure aligned chunks in OOC sort (#19118)
• Recursively align when converting to ArrowArray (#19097)
• Raise on invalid shape of shape 1, empty combination (#19113)
• Use two-pass algorithm for csv to ensure correctness and SIMDize more ~17% (#19088)
• Allow converting DatetimeOwned to ChunkedArray (#19094)
• Throw proper error for empty char params in scan_csv (#19100)
• Ensure parquet schema arg is propagated to IR (#19084)
• Only rewrite numeric ineq joins (#19083)
• Check validity of columns of keys/aggs in dsl->ir (#19082)
• Bitwise aggregations should ignore null values (#19067)
• Remove failing datetime subclass test (#19068)
• Fix ser/de PlSmallStr error (#19060)
• Remove failing temporal lit tests (#19056)
• Divide-by-zero in OOC sort (#19048)
• Ensure must_flush flag is not reset (#19046)
• Error node should be on top (#19045)
• Force nested struct missing equality (#19031)
• Fix invalid alias udf (#19021)
• Raise invalid predicate join_where (#19020)
• Fix nested flag of functions with multiple arguments (#19016)
• Fix projection pushdown bug in IEJOINS (#19015)
• Separate temporal tests (#19012)
• Return the truth values of ne_missing and eq_missing operations for struct instead of null (#18930)
• Fix struct broadcasting comparisons (#19003)
• Wrong result on when().then().otherwise() on struct when both result are broadcast (#19000)
• Improve literals for temporal subclasses (#18998)
• Ensure same fmt in Series/AnyValue to string cast (#18982)
• Return correct value for when().then().else() on structs when using first()\last() (#18969)
• IPC don't write variadic_buffer_counts in blocks, but only dictionaries (#18980)
• Respect allow_threading in TernaryExpr (#18977)
• Make join test order-agnostic (#18975)
• Window function had incorrect output name on ExprIR (#18970)
• Fix lit().shrink_dtype() broadcasting (#18958)
• Parallel evaluation of cumulative_eval (#18959)
• Properly implement AnyValue::Binary into_py (#18960)
• Fix Expr.over with order_by did not take effect if group keys were sorted (#18947)
• Properly fetch type of full None List Series (#18916)
• Incorrect mode for sorted input (#18945)
• Properly choose inner physical type for Array (#18942)
• Disable very old date in timezone test for CI (#18935)
• Infer reshape dims when determining schema (#18923)
• Incorrect broadcasting on list-of-string set ops (#18918)
• Adding with_row_index() to previously collected lazy scan does not take effect (#18913)
• Properly zip struct validities (#18886)
• Ensure ListPrimitiveBuilder dtype invariant is asserted (#18889)
• Out-of-bounds gather in categorical->int cast (#18897)
• AnyValue Series from Categorical/Enum (#18893)
• Properly cast AnyValue string (#18888)
• Fix SO in json inference (#18887)
• Use proper thread pool in cumulative_eval (#18885)
• Properly calculate duration units (#18869)
• Check values in strict cast Int to Time (#18854)
• Fix typo in DuplicateError error message (#18855)
• Properly merge live- and dead columns in prefiltered (#18862)
• DataFrame plot was raising when some extra keywords were passed to encodings (e.g. x=alt.X(a, axis=alt.Axis(labelAngle=30))) (#18836)
• Respect strictness in list constructor (#18853)
• Properly broadcast array arithmetic (#18851)
• Throw error for comparison of unequal length series (#18816)
• Raise when parquet file has extra columns and no select() was done (#18843)
• Replace DynArgs with an enum containing all its variants (#18746)
• Return empty DF when input is empty json list (#18827)
• Handle AnyValue::Struct to prevent null returns (#18801)
• Struct filter by index (#18778)
• Proper dtype casting for struct embedded categoricals in chunked categoricals (#18815)
• Fixed some error/assertion types (#18811)
• Remove panic in arr.to_struct (#18804)
• Allow empty sort by columns (#18774)
• Broadcast zip_with for structs (#18770)
• Dropped/shifted rows in parquet scan with streaming=True (#18766)
• Fix cum_max using exception text of cum_min for invalid dtype (#18780)
• Fix accidental raise on shape 1 (#18748)

📖 Documentation

• Fix docstrings for ATAN2 and ATAN2D SQL functions (#19351)
• Tiny correction post dask-expr (#19354)
• Remove ecosystem viz section since there is one in misc already (#18408)
• Fix typo in custom expressions docs (#19292)
• Add SQL docs for new QUANTILE_CONT and QUANTILE_DISC functions (#19272)
• Add marimo to ecosystem.md (#19250)
• Link to main website from banner (#19177)
• Fix example of as_struct (#19116)
• Clarify difference between bitwise/logical ops (#19180)
• Fix examples/read_csv rust example (#19185)
• Add non-equi joins to, and revise, joins docs page (#19127)
• Add Series.first,last,approx_n_unique to docs (#19146)
• Revise and improve 'Concepts' section (#19087)
• Fix example of lazy schema verification (#19059)
• Rewrite 'Getting started' page (#19028)
• Align dates in DataFrame example with Python (#18491)
• Fix is_not_nan description (#18985)
• Recommend targetDir for rust-analyzer (#18973)
• Typo for IntoDf trait (#18933)
• Fix broken user-guide API links (#18872)
• Fix minor rogue apostrophes (#18865)
• Fix link to issue tracker and code snippet format in GPU docs (#18850)
• Refactor docs directory hierarchy (#18773)
• Minor improvements to contributing guide (#18777)

📦 Build system

• Revert PyO3 version back to 0.21 (#19376)
• Bump Rust toolchain to nightly-2024-09-29 (#19006)
• Bump simd-json to 0.14 (#18999)

🛠️ Other improvements

• Undo conflicting fix (#19463)
• Remove code in examples folder in favor of the user guide (#19430)
• Add var/std support to new streaming engine (#19406)
• Add streaming groupby for reductions (#19291)
• Add AlignedBytes types (#19308)
• Don't pickle entire python function for object store keying (#19340)
• Add extra functionality to SharedStorage (#19361)
• Improve error message for Zero-Field Structs with Parquet (#19370)
• Add tracking of async task wait time statistics (#19373)
• Add capability to transmute to SharedStorage (#19353)
• Reduce memcopy in parquet (#19350)
• Purge arrow-rs support (#19312)
• Use size_of/align_of from prelude (#19311)
• Add/fix unordered row decode, change unordered format (#19284)
• Trim sliced-out memory from ListArrays in list arithmetic (#19276)
• Move from parquet-format-safe to polars-parquet-format (#19275)
• Purge unused code (#19267)
• Skip flaky test (#19242)
• Feature gate for list arithmetic (#19237)
• Add more tests for list arithmetic (#19225)
• Remove unused IPC async (#19223)
• Make get_list_builder infallible (#19217)
• Migrate to PyO3 0.22 and released verion of rust-numpy crate (#19199)
• Make expression output type known (#19195)
• Revert "feat(python): Raise an error when users try to use Polars API in a fork()-without-execve() child (#19149) (#19188)
• Zero-Field Structs and DataFrame with Height Property (#19123)
• Reduction -> GroupedReduction for the new streaming engine (#19176)
• Make pl.repeat part of the IR (#19152)
• Workaround for rust-analyzer bug (#19134)
• Minor CSV bit twiddle nitpick (#19121)
• Use row encoding in asof join (#19125)
• Remove deprecated raw_entry_mut in StringCache (#19126)
• Clean remove_prefix since python3.9 is now the minimum Python (#19070)
• Eliminate some uses of deprecated raw_entry (#19102)
• Migrate to hashbrown 0.15 (#19091)
• Pin hashbrown to 0.14 until migrated (#19076)
• Add new streaming engine to CI (#19051)
• Add WithRowIndexNode to new-streaming engine (#19037)
• Add buffers to zip heads to reduce contention (#19036)
• Fix race condition in DistributorChannel (#19033)
• Mark schema arg in read/scan_parquet as unstable (#19018)
• Fix new-streaming test_lazy_parquet::test_row_index (#19019)
• Preserve scalar in more places (#18898)
• Mention allow_missing_columns in error message when column not found (parquet) (#18972)
• Fix new-streaming test_lazy_parquet::test_row_index (#18978)
• Disable CSE-specific test on new streaming engine (#18971)
• Add FixedSizeList equality broadcasting (#18967)
• Divide ChunkCompare into Eq and Ineq variants (#18963)
• Another set of new-stream test skip/fixes (#18952)
• Fix/skip variety of new-streaming tests, cont (#18928)
• Fix/skip variety of new-streaming tests (#18924)
• Minor new-streaming test fixes (#18891)
• Make with_column_unchecked take Column (#18863)
• Keep scalar in more places (#18775)
• Replace DynArgs with an enum containing all its variants (#18746)
• Fix new-streaming test_parquet::test_complex_types (#18829)
• Fix zero-length len (#18817)
• Add panic to unchecked DataFrame constructors in debug mode (#18807)
• Add missing implicit datetime alias in ExprIR (#18809)
• Fix topological sort in new streaming engine (#18806)
• Fix new-streaming parquet test_row_index_projection_pushdown_18463 (#18805)
• Remove short-lived / non-CPU bound task spawns on async executor in new-streaming (#18764)
• Fix parquet file metadata is dropped after first DSL->IR conversion (#18789)
• Remove extra hashmap construction in new-streaming parquet (#18792)
• Fix new-streaming parquet on empty parquet (#18763)
• Ensure fallback node gets correct length df even if no columns selected (#18772)
• Fix input independence tests in new-streaming engine (#18771)
• Make DataFrame a Vec of Column instead of Series (#18664)
• Run benchmark on PR labeled 'needs-bench' (#18737)
• Add pre-filtered decode to new parquet source (#18715)
• Allow polars to pass cargo check on windows (#18672)
• Remove unsafe in polars-json deserialize code (#18725)

Thank you to all our contributors for making this release possible!
@3ok, @Bidek56, @LukasFolwarczny, @Manishearth, @MarcoGorelli, @Plutone11011, @Rashik-raj, @adamreeve, @aleexharris, @alexander-beedie, @alonme, @balbok0, @barak1412, @beckernick, @benrutter, @bradfordlynch, @cmdlineluser, @coastalwhite, @corleyma, @corwinjoy, @deanm0000, @dependabot, @dependabot[bot], @dvillaveces, @edwinvehmaanpera, @eitsupi, @etrotta, @gab23r, @i64, @itamarst, @janscholten, @jbutterwick, @joelostblom, @kenkoooo, @kgv, @khalidmammadov, @laurentS, @max-muoto, @mcrumiller, @mscolnick, @nameexhaustion, @npielawski, @orlp, @pomo-mondreganto, @r-brink, @ritchie46, @rodrigogiraoserrao, @siddharth-vi, @squnit, @stinodego, @sunadase, @t-ded, @wakabame, @wence-, @wolfgang-noichl and @xhiroga