Read the contributing guidelines

STYLE replace flake8-rst with something maintained Code Style good first issue

#46865 opened Apr 25, 2022 by MarcoGorelli

DOC: write guide for how to replace append Docs good first issue

#46825 opened Apr 21, 2022 by MarcoGorelli

1

WEB: Use mambaforge for the getting started installation instructions? Needs Discussion good first issue Web

#46793 opened Apr 17, 2022 by datapythonista

3

Add interactive terminal to pandas website good first issue Web

#46682 opened Apr 7, 2022 by datapythonista

13

DOC: documentation on `.loc[]` needs some clarification Docs good first issue

#46620 opened Apr 3, 2022 by kwhkim

3

BUG: DataFrame.replace with dict doesn't work when value=None Docs good first issue DataFrame replace

#46606 opened Apr 1, 2022 by zeromh

5

BUG: pandas.io.formats.style.Styler.to_excel doesn't support storage_options as its documented Bug IO Excel good first issue Styler

#46381 opened Mar 15, 2022 by jcunhafonte

9

DOC: index and dropna docs missing from to_hdf docstring Docs IO HDF5 good first issue

#45030 opened Dec 23, 2021 by phofl

4

BUG: validate_docstrings has many warnings Docs good first issue Warnings

#44642 opened Nov 27, 2021 by TomAugspurger

8

BUG: changed behavior of df.loc on multiindex since 1.3.0 Indexing MultiIndex good first issue Needs Tests

#43599 opened Sep 16, 2021 by auderson

5

BUG: `DataFrame.to_parquet` doesn't round-trip pyarrow StringDtype Docs Strings IO Parquet good first issue

#42664 opened Jul 22, 2021 by TomAugspurger

7

ENH/CI: Cache packages installed from conda Enhancement Performance CI good first issue

#42580 opened Jul 17, 2021 by lithomas1

4

STYLE Investigate restructuredtext_lint as pre-commit hook Code Style good first issue

#41986 opened Jun 13, 2021 by MarcoGorelli

3

STYLE add check for future annotations Code Style good first issue

#41901 opened Jun 9, 2021 by MarcoGorelli

21

DOC: Additional items for the cheat sheet Docs good first issue

#40680 opened Mar 29, 2021 by Dr-Irv

28

ENH: consistency of input args for boundaries Master Tracker Needs Discussion good first issue API - Consistency

#40245 opened Mar 5, 2021 by attack68

15

DOC: add button to edit on GitHub Docs Needs Discussion good first issue

#39859 opened Feb 17, 2021 by afeld

14

DOC: Reindexing behaviour of dataframe column-assignment missing Docs Indexing good first issue

#39845 opened Feb 16, 2021 by fish-face

7

BUG: Concatenating categorical datetime columns raises a ValueError since v1.2 good first issue Needs Tests

#39443 opened Jan 27, 2021 by aiudirog

11

BUG: df.plot.barh() broken from 1.1.5 to 1.2 under specific circumstances Visualization Regression Duplicate Report good first issue Needs Tests

#39126 opened Jan 12, 2021 by LarsWigger

5

DOC: add comparison to spreadsheets Docs IO Excel good first issue

#38990 opened Jan 6, 2021 by afeld

9

REGR: Bar plot from Series with IntervalIndex fails in pandas 1.2.0 Visualization Regression good first issue Needs Tests

#38969 opened Jan 5, 2021 by venaturum

15

BUG: Augmented arithmetic assignments will modify original series starting version 1.1.4 Docs good first issue Copy / view semantics

#38519 opened Dec 16, 2020 by nikita-ivanov

8

TYP: investigate/fix ignored mypy errors good first issue Typing

#37715 opened Nov 9, 2020 by simonjayhawkins

19

BUG: iterrows encounters OverflowError with str and datetime64[ns] columns Regression Timedelta good first issue Needs Tests

#35665 opened Aug 11, 2020 by allentsouhuang

6

DOC: `.str.cat` output in case of `Index` object Docs good first issue

#35556 opened Aug 4, 2020 by galipremsagar

7

BUG: read_sql no longer works simply with SqlAlchemy selectables and a quick fix IO SQL good first issue Needs Tests

#35484 opened Jul 30, 2020 by machow

4

BUG: grouping with categorical interval columns good first issue Needs Tests

#34164 opened May 13, 2020 by antipisa

8

BUG: Multiindex.nunique raises NotImplementedError Missing-data MultiIndex good first issue Needs Tests

#34019 opened May 6, 2020 by mizuy

4

DOC: Single Document For Code Guidelines Docs Code Style good first issue

#33851 opened Apr 28, 2020 by Stockfoot

19

Groupby multiple columns causes agg to have precision loss on int64 Groupby Dtype Conversions good first issue Needs Tests

#33234 opened Apr 2, 2020 by Lawrr

4

Quantile function fails when performing groupby on Time Zone Aware Timestamps Groupby Timezones good first issue Needs Tests

#33168 opened Mar 31, 2020 by jlandercy

5

Incorrect dtype for concat with empty float and datetime columns Bug Reshaping Dtype Conversions good first issue Needs Tests

#32934 opened Mar 23, 2020 by TomAugspurger

5

dtype change when doing operations on dataframes good first issue Needs Tests NA - MaskedArrays

#32822 opened Mar 19, 2020 by thedimlebowski

9

Fix capitalization among headings in documentation files Docs good first issue

#32550 opened Mar 9, 2020 by tonywu1999

33

Grouping by all columns of an empty DataFrame should produce MultiIndex, but doesn't Groupby MultiIndex good first issue Needs Tests

#32464 opened Mar 5, 2020 by shwina

2

WEB: Multiple "Getting Started" on pandas.io leads to different links good first issue Web

#32307 opened Feb 27, 2020 by mroeschke

9

Inconsistent behavior when DataFrame with strings and None is created from lists or dictionary. good first issue Needs Tests

#32218 opened Feb 24, 2020 by ace-e4s

6

pd.where OverflowError with large numbers Dtype Conversions good first issue Needs Tests

#31687 opened Feb 5, 2020 by wailashi

14

dtype does not get set to object when adding column with df.at[...] = ['some list'] Indexing good first issue Needs Tests

#30649 opened Jan 3, 2020 by McToel

4

DOC: Remove and disable wiki Docs good first issue

#30410 opened Dec 22, 2019 by datapythonista

5

Move 'For Developers' content from wiki to contributing docs. Docs good first issue

#30232 opened Dec 12, 2019 by simonjayhawkins

19

BUG: IntervalIndex.get_indexer fails for homogeneous Period targets Indexing Period Interval good first issue Needs Tests

#30178 opened Dec 10, 2019 by jschendel

2

DOC: Remove :okwarning: from scale guide when used dask version is not raising FutureWarning anymore Docs good first issue

#29960 opened Dec 2, 2019 by SaturnFromTitan

DataFrame.at indexing with date string promotes column type, while indexing with datetime casts value Timeseries Indexing Dtype Conversions good first issue Needs Tests

#29709 opened Nov 19, 2019 by Jokab

2

Series.rmod called with scalar returns inconsistent results based on size of series Numeric Operations good first issue Needs Tests

#29602 opened Nov 13, 2019 by kmacdough

5

Misleading error messages when opening inexistent json file Enhancement Error Reporting IO JSON good first issue

#29102 opened Oct 19, 2019 by datapythonista

14

pandas pivot_table aggfunc/values parameters behaving oddly Reshaping good first issue Needs Tests

#29080 opened Oct 18, 2019 by it176131

2

Inconsistent processing of NaT values by GroupBy Groupby Missing-data good first issue Needs Tests

#29036 opened Oct 16, 2019 by sergiykhan

6

Resample on MultiIndex level takes much more time than on normal column MultiIndex Resample good first issue Benchmark

#28635 opened Sep 26, 2019 by pgrudzinski

3

Various methods don't call call __finalize__ Bug good first issue metadata

#28283 opened Sep 4, 2019 by TomAugspurger

37

DataFrame.drop with empty DatetimeIndex behaves differently than passing empty Index good first issue Needs Tests DataFrame

#27994 opened Aug 18, 2019 by katsuya-horiuchi

9

DOC: Fix formatting errors in docstrings Docs good first issue

#27977 opened Aug 17, 2019 by datapythonista

9

Fix PR02 issues in docstrings Docs good first issue

#27976 opened Aug 17, 2019 by datapythonista

15

Filtering dataframe with sparse column leads to NAs in sparse column Regression Sparse good first issue Needs Tests

#27781 opened Aug 6, 2019 by stelsemeyer

17

Inconsistent dtype changes between multi-column assignment and single-column assignment Indexing Dtype Conversions good first issue Needs Tests

#27583 opened Jul 25, 2019 by howsiwei

2

Adhere to the standard for dropping Python versions Docs Dependencies good first issue

#27557 opened Jul 24, 2019 by datapythonista

8

Indexing on series where index is output from pd.cut Indexing good first issue Needs Tests

#27437 opened Jul 17, 2019 by kuchenrolle

2

DataFrame.sum() with mix of timedelta and IntegerNA returns NA for IntNA Missing-data Numeric Operations good first issue Needs Tests NA - MaskedArrays Reduction Operations

#27185 opened Jul 2, 2019 by TomAugspurger

3

Performance issue when replacing a sting column with integer Indexing good first issue Benchmark

#26889 opened Jun 16, 2019 by rc-eddy

9

BUG: groupby.transform doesn't raise on missing arguments Groupby good first issue Needs Tests

#26840 opened Jun 14, 2019 by ghost

8

Handle numpy.matmul in DataFrame.__array_ufunc__ Numeric Operations good first issue Needs Tests ufuncs

#26650 opened Jun 4, 2019 by nate-bryant

3

BUG: pivot_table with margins=True and numeric columns is buggy Reshaping Numeric Operations good first issue Needs Tests

#26568 opened May 29, 2019 by jschendel

3

numpy ravel does not work on a list of DataFrames with specified column names Compat good first issue Needs Tests DataFrame

#26247 opened Apr 30, 2019 by cod3licious

6

AWS_S3_HOST environment variable no longer available Docs IO Network good first issue

#26195 opened Apr 23, 2019 by jakobkogler

4

Non-unique integer index performance depending on index creation method good first issue Benchmark

#26064 opened Apr 12, 2019 by quantuminternet

2

Logical operations on np.bool_ using pandas.eval raises TypeError good first issue Needs Tests expressions

#25823 opened Mar 21, 2019 by james-mchugh

6

Different behavior of to_replace method between pandas version 0.23.4 and 0.24.2 by changing dtype of series Missing-data Dtype Conversions good first issue Needs Tests replace

#25797 opened Mar 20, 2019 by oliverfu89

3

Extremely Slow `Block.setitem()` when `value` is a builtin python type. Indexing good first issue Benchmark

#25756 opened Mar 17, 2019 by kykosic

5

Inconsistent behavior when using GroupBy and pandas.Series.mode Groupby good first issue Needs Tests

#25581 opened Mar 7, 2019 by jointfull

8

"SpecificationError: nested dictionary is ambiguous in aggregation" in a certain case of groupby-aggregation Groupby good first issue Needs Tests

#25471 opened Feb 28, 2019 by Khris777

4

crosstab shows margins in wrong order if index/columns are ordered categories Reshaping good first issue Needs Tests

#25278 opened Feb 12, 2019 by oriolmirosa

2

Indexing bug with Sparse DataFrames and column names not starting with `0` Sparse good first issue Needs Tests

#25270 opened Feb 11, 2019 by rasbt

7

Intersection of MultiIndexes reports incorrect lexsort_depth MultiIndex good first issue Needs Tests setops

#25169 opened Feb 5, 2019 by toobaz

2

Float conversion makes fillna lossy good first issue Needs Tests

#24537 opened Jan 1, 2019 by jbrockmendel

6

BUG: loc behaves incorrectly on PeriodIndex within MultiIndex with 3 levels good first issue Needs Tests

#24091 opened Dec 4, 2018 by PAeberhard

7

column names with leading underscores with df.itertuples cause AttributeError when accessed good first issue Needs Tests

#23848 opened Nov 21, 2018 by gitstb

6

Data type of new assigned DataFrame column good first issue Needs Tests

#23326 opened Oct 25, 2018 by gitwhistle

3

ENH: Allow use of keep="all" in duplicated Enhancement Needs Discussion good first issue duplicated

#23251 opened Oct 20, 2018 by svenharris

7

pandas.cut: the 'include_lowest' argument isn't behaving as documented Docs good first issue cut

#23164 opened Oct 15, 2018 by evarga

7

DOC: Generating docs doesn't work if path has whitespaces Docs good first issue

#22836 opened Sep 26, 2018 by datapythonista

15

read_fwf: skip_blank_lines does nothing good first issue Needs Tests

#22693 opened Sep 13, 2018 by ivanradicek

7

unique aggregation unexpectedly returning different type good first issue Needs Tests

#22558 opened Sep 1, 2018 by ibackus

4

columns comparison with Enum column name triggers TypeError good first issue Needs Tests

#22551 opened Aug 31, 2018 by s-wakaba

7

assert_series_equal(..., check_exact=True) reports identically constructed Series are not equal. good first issue Needs Tests

#22400 opened Aug 17, 2018 by RhysU

3

Cannot pickle parser functions? good first issue Needs Tests

#22265 opened Aug 9, 2018 by smcveigh-phunware

5

MultiIndex Bug Copying Values Incorrectly When Adding Values To Index good first issue Needs Tests

#22247 opened Aug 8, 2018 by JonahJ

3

DataFrame.groupby()[col].transform() tries to convert result to original column type good first issue Needs Tests

#22243 opened Aug 8, 2018 by mfripp

2

"TypeError: unorderable types" in Python3 when index values are dict keys of tuples or tuples with non-homogeneous dtypes good first issue Needs Tests

#22077 opened Jul 27, 2018 by toobaz

6

BUG: Column-major DataFrames stored in HDFStore are returned as row-major IO HDF5 good first issue Needs Tests

#22073 opened Jul 27, 2018 by wesm

3

Updating value of a single row of a column using loc or at fails good first issue Needs Tests

#22040 opened Jul 24, 2018 by abhinav-upadhyay

8

pivot_table produces inconsistent columns if applied to empty table good first issue Needs Tests

#21932 opened Jul 16, 2018 by ischurov

2

Importing pandas changes return value of sys.getsizeof? good first issue Needs Tests

#21758 opened Jul 6, 2018 by danieljacobs1

8

ENH/API: allow different values for labels/index in DF.reindex __OR__ raise error Error Reporting good first issue

#21685 opened Jun 29, 2018 by h-vetinari

13

BUG: .values for objects containing categoricals with box-able categories good first issue Needs Tests

#21658 opened Jun 27, 2018 by jorisvandenbossche

1

Tick DateOffset Normalize whatsnew entry has an error Docs Frequency good first issue

#21564 opened Jun 20, 2018 by TomAugspurger

13

pandas dataframe to_json(orient='split') change uint64 to negative int good first issue Needs Tests

#21073 opened May 16, 2018 by yamyamyuo

3

Unexpected results when filtering with .isin (some fields contain python datastructures) good first issue Needs Tests

#20883 opened Apr 30, 2018 by atc0m

11

DataFrame.groupby.sum() is extremely slow when dtype is timedelta64[ns] compared to int64. good first issue Benchmark

#20660 opened Apr 11, 2018 by wezzman

10

Assign back converted multiple columns to datetime failed Indexing good first issue Needs Tests

#20511 opened Mar 28, 2018 by jesrael

8

Move Wiki testing page to main docs? Docs good first issue

#20501 opened Mar 27, 2018 by TomAugspurger

3

issue when shifting with Timedelta in a groupby Docs Groupby Timedelta good first issue

#20492 opened Mar 26, 2018 by randomgambit

11

DataFrame.from_dict multilevel dicts with datetime.date objects as keys sets the values as NaN in the DataFrame good first issue Needs Tests

#19993 opened Mar 5, 2018 by hodossy

10

slow execution with internal error visible upon interruption for indexing with dataframe: TypeError: cannot convert bool to an floatblock good first issue Needs Tests

#19791 opened Feb 20, 2018 by denfromufa

3

API: Should factorize(categorical) return a Categorical for uniques? good first issue Needs Tests

#19721 opened Feb 15, 2018 by TomAugspurger

15

ENH: Index should have diff() method Enhancement good first issue Index

#19708 opened Feb 15, 2018 by jbrockmendel

9

DataFrame.__setitem__ performance regression with object dtype Indexing good first issue Benchmark

#19299 opened Jan 18, 2018 by TomAugspurger

2

Document our pytest fixtures Testing Docs good first issue

#19159 opened Jan 9, 2018 by TomAugspurger

16

Raise ValueError for read_json and orient='table' With Numeric Column Names Enhancement Error Reporting IO JSON good first issue

#19129 opened Jan 8, 2018 by WillAyd

14

DatetimeIndex comparison with ndim>1 incorrect or raises Numeric Operations good first issue Needs Tests

#19088 opened Jan 5, 2018 by jbrockmendel

3

BUG: Creating Index name using `names` names argument, doesn't set index name Docs MultiIndex good first issue

#19082 opened Jan 4, 2018 by jsnowacki

5

DOC: improve docs for broadcasting behavior Docs Numeric Operations good first issue

#18857 opened Dec 19, 2017 by jakevdp

12

ddof for np.std in df.agg changes depending on how given & lambda expression does not work correctly in a list of functions good first issue Needs Tests

#18734 opened Dec 11, 2017 by yuzie007

3

Groupby with function returning a tuple fails if index has a name Docs Groupby good first issue

#18696 opened Dec 8, 2017 by achabotl

7

Reading a SAS file with 0 rows gives None Bug Error Reporting IO SAS good first issue

#18198 opened Nov 9, 2017 by AbdealiJK

10

df autosorts rows on construction with OrderedDict of OrderedDicts good first issue Needs Tests

#18166 opened Nov 8, 2017 by bjonen

3

DOC: nice links / examples for setting with copy & aggregation Docs good first issue

#17505 opened Sep 13, 2017 by jreback

2

DOC: use shared_docs for isna/notna & isnull/notnull Docs Missing-data good first issue

#17096 opened Jul 27, 2017 by jreback

9

DOC: section on caveats of storing lists inside DataFrame/Series Docs good first issue Nested Data

#17027 opened Jul 19, 2017 by chris-b1

12

Scatter plot with colour_by and size_by variables Docs Visualization good first issue

#16827 opened Jul 5, 2017 by nipunbatra

9

inplace kwarg must be of bool type, but other boolean kwargs don't have this restriction Enhancement Error Reporting good first issue API - Consistency inplace

#16714 opened Jun 16, 2017 by colinmorris

7

DOC: pivot function Docs Reshaping good first issue

#16578 opened Jun 2, 2017 by jesrael

4

Non-inclusive partial string indexing on DatetimeIndex Docs Timeseries Indexing good first issue

#16571 opened Jun 1, 2017 by linar-jether

6

Importing pandas module breaks expected behavior of Thread[ed] script good first issue Needs Tests

#16544 opened May 31, 2017 by christian-eriksson

5

IndexError raised on invalid csv file good first issue Needs Tests

#16393 opened May 19, 2017 by Dominik1123

8

pd.crosstab, categorical data and missing instances Docs Reshaping Categorical good first issue

#16367 opened May 16, 2017 by peisenha

15

Documentation on Performance considerations Docs Performance good first issue

#16310 opened May 9, 2017 by Dr-Irv

3

Wrong error message in HDFStore.append when appending dataframe with None item in previously string-only column Enhancement Error Reporting IO HDF5 good first issue

#16300 opened May 9, 2017 by toobaz

6

no warning with invalid pd.set_option('display.max_colwidth') Enhancement Output-Formatting Error Reporting good first issue

#16097 opened Apr 22, 2017 by jkornblum

5

DOC: inconsistent docs-string signatures for shared functions Docs good first issue

#15609 opened Mar 7, 2017 by jreback

6

DOC: overall improvement of docstrings Docs good first issue

#15580 opened Mar 5, 2017 by jorisvandenbossche

11

cannot get cut() to display desired bins label Docs Numeric Operations good first issue cut

#15357 opened Feb 9, 2017 by qAp

5

Multiarray searchsorted fails Enhancement Error Reporting MultiIndex good first issue

#14833 opened Dec 8, 2016 by Anaphory

13

DOC: min_itemsize for HDFStore append for encoded strings Docs Usage Question IO HDF5 good first issue

#14601 opened Nov 7, 2016 by johanneshk

6

DOC: more documentation that pandas by-default aligns when setting Docs Indexing good first issue

#13950 opened Aug 9, 2016 by IamGianluca

2

ERR: Categoricals should not allow non-strings when an object dtype is passed Enhancement Error Reporting IO HDF5 Categorical good first issue

#13919 opened Aug 5, 2016 by hnykda

12

ERR: more informative error messages on invalid freq for Period when they are point-in-time Enhancement Error Reporting Frequency good first issue

#13871 opened Aug 1, 2016 by agraboso

4

DOC: floating point precision on writing/reading to csv Docs IO CSV good first issue

#13159 opened May 12, 2016 by FBartlett

4

append a categorical with different categories to the existing Docs Categorical good first issue

#12509 opened Mar 2, 2016 by dneise

3

Misaligned shared axes between timeseries plots of different frequency. good first issue Needs Tests

#11574 opened Nov 11, 2015 by juseg

4

DOC: document optional arguments on plot submethods Docs Visualization good first issue

#11042 opened Sep 10, 2015 by shoyer

1

read_sql should accept a sql_params parameter Docs IO SQL good first issue

#10899 opened Aug 24, 2015 by scls19fr

10

DOC/ERR: better error message on unsuccessful datetime parsing Enhancement Timeseries Error Reporting good first issue

#10720 opened Aug 1, 2015 by jreback

14

DOC: splitting the IO docs into separate pages Docs good first issue

#10446 opened Jun 26, 2015 by jorisvandenbossche

1

With an external grouper, there is no way to access the grouped value in a DataFrame(...).groupby(...).apply(...) workflow Docs Groupby good first issue

#9545 opened Feb 24, 2015 by brianthelion

13

DOC/BUG? pivot functionality confusing/inconsistent Docs Reshaping good first issue

#8160 opened Sep 2, 2014 by seth-p

2

DOC: improve groupby reference docs Docs Groupby Master Tracker good first issue

#6944 opened Apr 23, 2014 by jorisvandenbossche

4

DOC: freeze old whatsnew notes? Docs good first issue

#6856 opened Apr 10, 2014 by jorisvandenbossche

17

DOC: update groupby NA group handing / workaround Docs Groupby good first issue

#5456 opened Nov 6, 2013 by mkeller-upb

5

Give the merge copy parameter better documentation Docs good first issue

#4599 opened Aug 18, 2013 by cpcloud

6

DOC: Unclear documentation for Period Construction Docs Frequency good first issue

#4591 opened Aug 17, 2013 by cancan101

7