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PyKX Changelog

Note

The changelog presented here outlines changes to PyKX when operating within a Python environment specifically, if you require changelogs associated with PyKX operating under a q environment see here.

Warning

Currently PyKX is not compatible with Pandas 2.2.0 or above as it introduced breaking changes which cause data to be cast to the incorrect type.

PyKX 2.4.2

Release Date

2024-04-03

Fixes and Improvements

  • Updated libq to 2024.03.28 for all supported OS's.

PyKX 2.4.1

Release Date

2024-03-27

Fixes and Improvements

  • Previously calls to qsql.select, qsql.exec, qsql.update and qsql.delete would require multiple calls to parse the content of where, colums and by clauses. These have now been removed with all parsing now completed within the functional query when called via IPC or local to the Python process.

  • Linux x86 and Mac x86/ARM unlicensed mode e.o library updated to 2023.11.22. Fixes subnormals issue:

    >>> import os
>>> os.environ['PYKX_UNLICENSED']='true'
>>> import pykx as kx
>>> import numpy as np
>>> np.finfo(np.float64).smallest_subnormal + 0.
/usr/local/anaconda3/lib/python3.8/site-packages/numpy/core/getlimits.py:518: UserWarning: The value of the smallest subnormal for <class 'numpy.float64'> type is zero.
setattr(self, word, getattr(machar, word).flat[0])
/usr/local/anaconda3/lib/python3.8/site-packages/numpy/core/getlimits.py:89: UserWarning: The value of the smallest subnormal for <class 'numpy.float64'> type is zero.
return self._float_to_str(self.smallest_subnormal)
0.0
    >>> import os
>>> os.environ['PYKX_UNLICENSED']='true'
>>> import pykx as kx
>>> import numpy as np
>>> np.finfo(np.float64).smallest_subnormal + 0.
5e-324

PyKX 2.4.0

Release Date

2024-03-20

Additions

  • Support for q/kdb+ 4.1 documentation here added as an opt-in capability, this functionality is enabled through setting PYKX_4_1_ENABLED environment variable.

    >>> import os
>>> os.environ['PYKX_4_1_ENABLED'] = 'True'
>>> import pykx as kx
>>> kx.q.z.K
pykx.FloatAtom(pykx.q('4.1'))

  • Added support for Python 3.12.

    • Support for PyArrow in this python version is currently in Beta.
  • Added conversion of NumPy arrays of type datetime64[s], datetime64[ms], datetime64[us] to kx.TimestampVector
  • Added Table.sort_values(), Table.nsmallest() and Table.nlargest() to the Pandas like API for sorting tables.
  • Table.rename() now supports non-numerical index columns and improved the quality of errors thrown.

  • Added the reconnection_attempts key word argument to SyncQConnection, SecureQConnection, and AsyncQConnection IPC classes. This argument allows IPC connection to be automatically re-established when it is lost and a server has reinitialized.

    >>> import pykx as kx
>>> conn = kx.SyncQConnection(port = 5050, reconnection_attempts=4)
>>> conn('1+1')    # Following this call the server on port 5050 was closed for 2 seconds
pykx.LongVector(pykx.q('2'))
>>> conn('1+2')
WARNING: Connection lost attempting to reconnect.
Failed to reconnect, trying again in 0.5 seconds.
Failed to reconnect, trying again in 1.0 seconds.
Connection successfully reestablished.
pykx.LongAtom(pykx.q('3'))

  • Added --reconnection_attempts option to Jupyter %%q magic making use of the above IPC logic changes.

  • Addition of environment variable/configuration value PYKX_QDEBUG which allows debugging backtrace to be displayed for all calls into q instead of requiring a user to specify debugging is enabled per-call. This additionally works for remote IPC calls and utilisation of Jupyter magic commands.

    >>> import pykx as kx
>>> kx.q('{x+1}', 'e')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/anaconda3/lib/python3.8/site-packages/pykx/embedded_q.py", line 230, in __call__
    return factory(result, False)
  File "pykx/_wrappers.pyx", line 493, in pykx._wrappers._factory
  File "pykx/_wrappers.pyx", line 486, in pykx._wrappers.factory
pykx.exceptions.QError: type
>>> kx.q('{x+1}', 'e', debug=True)
backtrace:
  [2]  {x+1}
         ^
  [1]  (.Q.trp)

  [0]  {[pykxquery] .Q.trp[value; pykxquery; {if[y~();:(::)];2@"backtrace:
                    ^
",.Q.sbt y;'x}]}
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/anaconda3/lib/python3.8/site-packages/pykx/embedded_q.py", line 230, in __call__
    return factory(result, False)
  File "pykx/_wrappers.pyx", line 493, in pykx._wrappers._factory
  File "pykx/_wrappers.pyx", line 486, in pykx._wrappers.factory
pykx.exceptions.QError: type
    >>> import os
>>> os.environ['PYKX_QDEBUG'] = 'True'
>>> import pykx as kx
>>> kx.q('{x+1}', 'e')
backtrace:
  [2]  {x+1}
         ^
  [1]  (.Q.trp)

  [0]  {[pykxquery] .Q.trp[value; pykxquery; {if[y~();:(::)];2@"backtrace:
                    ^
",.Q.sbt y;'x}]}
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/anaconda3/lib/python3.8/site-packages/pykx/embedded_q.py", line 230, in __call__
    return factory(result, False)
  File "pykx/_wrappers.pyx", line 493, in pykx._wrappers._factory
  File "pykx/_wrappers.pyx", line 486, in pykx._wrappers.factory
pykx.exceptions.QError: type

Fixes and Improvements

  • Added instructions for script to install Windows dependencies.

  • Resolved segfaults on Windows when PyKX calls Python functions under q.

    >>> import pykx as kx
>>> kx.q('{[f;x] f  x}', sum, kx.q('4 4#til 16'))

Sorry, this application or an associated library has encountered a fatal error and will exit.
If known, please email the steps to reproduce this error to tech@kx.com
with a copy of the kdb+ startup banner and the info printed below.
Thank you.
Fault address 0000000066110980
    >>> import pykx as kx
>>> kx.q('{[f;x] f  x}', sum, kx.q('4 4#til 16'))

pykx.LongVector(pykx.q('24 28 32 36'))

  • Updated kdb Insights Core libraries to 4.0.8, see here for more information.

  • Updated libq 4.0 version to 2024.03.04 for all supported OS's.

  • Fix issue where use of valid C backed q code APIs could result in segmentation faults when called.

    >>> import pykx as kx
>>> isf = kx.q('.pykx.util.isf')
>>> isf
pykx.Foreign(pykx.q('code'))
>>> isf(True)
Sorry, this application or an associated library has encountered a fatal error and will exit.
If known, please email the steps to reproduce this error to tech@kx.com
with a copy of the kdb+ startup banner and the info printed below.
Thank you.
SIGSEGV: Fault address 0x85
    >>> import pykx as kx
>>> isf = kx.q('.pykx.util.isf')
>>> isf
pykx.Foreign(pykx.q('code'))
>>> isf(True)
pykx.BooleanAtom(pykx.q('0b'))

  • Fixed error since 2.2.1 in unlicensed mode when converting TimestampVector containing nulls to Python.

    >>> conn('enlist 0Np').py()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/rocuinneagain/.local/lib/python3.10/site-packages/pykx/wrappers.py", line 2443, in py
        converted_vector[i]=q('0Np')
File "/home/rocuinneagain/.local/lib/python3.10/site-packages/pykx/embedded_q.py", line 216, in __call__
        raise LicenseException("run q code via 'pykx.q'")
pykx.exceptions.LicenseException: A valid q license must be in a known location (e.g. `$QLIC`) to run q code via 'pykx.q'.
    >>> conn('enlist 0Np').py()
[pykx.TimestampAtom(pykx.q('0Np'))]

  • Each call to the PyKX query API interned 3 new unique symbols. This has now been removed.

  • When using pykx.schema.builder users could not make use of pykx.*Vector objects for defining column types. This could result in confusion due to support for these types in other areas of the library (type casting etc).

    >>> pykx.schema.builder({'x': pykx.LongVector, 'x1': pykx.LongAtom})
Exception: Error: <class 'KeyError'> raised for column x error
    >>> pykx.schema.builder({'x': pykx.LongVector, 'x1': pykx.LongAtom})
pykx.Table(pykx.q('
x x1
----
'))

  • Application of astype conversions could error if attempting to convert the column of a dataset to it's current type, this could be raised if using astype explicitly or when used internal to PyKX such as when defining the expected type when reading a CSV file.

  • PyKX database table listing now uses kx.q.Q.pt instead of kx.q.tables() when presenting the available tables to a users, this more accurately reflects the tables that can be interacted with by a users within the process.

    >>> tab = kx.Table(data = {'sym': ['a', 'b', 'c'], 'num': [1, 2, 3]})
>>> tab.astype({'sym': kx.SymbolAtom})
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/anaconda3/lib/python3.8/site-packages/pykx/embedded_q.py", line 229, in __call__
    return factory(result, False)
  File "pykx/_wrappers.pyx", line 493, in pykx._wrappers._factory
  File "pykx/_wrappers.pyx", line 486, in pykx._wrappers.factory
pykx.exceptions.QError: type
    pykx.Table(pykx.q('
sym num
-------
a   1
b   2
c   3
'))

  • Fix to ensure that if set PYKX_Q_LIB_LOCATION is used as the value for QHOME when initializing PyKX. This ensures all symlinking happens in the expected location and that \l loading of files behaves correctly.

  • Renamed labels parameter in Table.rename() to mapper to match Pandas. Added deprecation warning to labels.

  • Fixed bug where keys were being enlisted when Table.rename() called.

    >>> tab = kx.KeyedTable(data=kx.q('([] Policy: 1 2 3)'))
>>> tab.rename(index={0:'a'})
idx     Policy
--------------
,`a     1
,1      2
,2      3
    >>> tab = kx.KeyedTable(data=kx.q('([] Policy: 1 2 3)'))
>>> tab.rename(index={0:'a'})
idx     Policy
--------------
`a      1
1       2
2       3

  • Deprecation of type column in dtypes output as it is a reserved keyword. Use new datatypes column instead.

  • Query API merge method no longer attempts to automatically key/unkey input tables when q_join=True. Users must pass correctly formed inputs.

    >>> import pykx as kx
>>> tab1 = kx.Table(data={'k': ['foo', 'bar', 'baz', 'foo'], 'v': [1, 2, 3, 5]})
>>> tab2 = kx.Table(data={'k': ['foo', 'bar', 'baz', 'foo'], 'v': [5, 6, 7, 8]})
>>> tab1_keyed = tab1.set_index('k')
>>> tab1.merge(tab2, how='left', q_join=True)
    >>> tab1.merge(tab2_keyed, how='left', q_join=True)

Beta Features

  • Addition of Compress and Encrypt classes to allow users to set global configuration and for usage within Database partition persistence.

    >>> import pykx as kx
>>> compress = kx.Compress(algo=kx.CompressionAlgorithm.gzip, level=8)
>>> kx.q.z.zd
pykx.Identity(pykx.q('::'))
>>> compress.global_init()
pykx.LongVector(pykx.q('17 2 8'))
>>> encrypt = kx.Encrypt(path='/path/to/the.key', password='PassWord')
>>> encrypt.load_key()
    >>> import pykx as kx
>>> compress = kx.Compress(algo=kx.CompressionAlgorithm.lz4hc, level=10)
>>> db = kx.DB(path='/tmp/db')
>>> db.create(kx.q('([]10?1f;10?1f)', 'tab', kx.q('2020.03m'), compress=compress)
>>> kx.q('-21!`:/tmp/db/2020.03/tab/x')
pykx.Dictionary(pykx.q('
compressedLength  | 140
uncompressedLength| 96
algorithm         | 4i
logicalBlockSize  | 17i
zipLevel          | 10i
'))

  • On Windows from version 2.3.0 PyKX would raise the following warning message at startup about incompatibility between Threading feature and Windows, this now is only raised when PYKX_THREADING is set.

    C:\Users\username\AppData\Roaming\Python\Python311\site-packages\pykx\config.py:220: UserWarning: PYKX_THREADING is only supported on Linux / MacOS, it has been disabled.
warn('PYKX_THREADING is only supported on Linux / MacOS, it has been disabled.')

PyKX 2.3.2

Release Date

2024-02-12

Fixes and Improvements

  • Update of PyKX 4.0 linux shared object to version 2024.02.09, this update is to facilitate deployments on more secure linux/linux-arm environments.
  • Update Table.rename() to skip over columns not in table instead of throwing error to match pandas.

PyKX 2.3.1

Release Date

2024-02-07

Fixes and Improvements

  • Python functions saved to q would error if passed '' or '.'. These now pass without issue.

    >>> def func(n=2):
...     return n
...
>>> kx.q['func']= func
>>> kx.q('func', '')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/rocuinneagain/.local/lib/python3.10/site-packages/pykx/embedded_q.py", line 227, in __call__
    return factory(result, False)
File "pykx/_wrappers.pyx", line 493, in pykx._wrappers._factory
File "pykx/_wrappers.pyx", line 486, in pykx._wrappers.factory
pykx.exceptions.QError: Provided foreign object is not a Python object
>>> kx.q('func', '.')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/rocuinneagain/.local/lib/python3.10/site-packages/pykx/embedded_q.py", line 227, in __call__
    return factory(result, False)
File "pykx/_wrappers.pyx", line 493, in pykx._wrappers._factory
File "pykx/_wrappers.pyx", line 486, in pykx._wrappers.factory
pykx.exceptions.QError: rank
    >>> def func(n=2):
...     return n
...
>>> kx.q['func']= func
>>> kx.q('func', '')
pykx.SymbolAtom(pykx.q('`'))
>>> kx.q('func', '.')
pykx.SymbolAtom(pykx.q('`.'))

  • Changed Table.rename() to ignore any columns values that are of the wrong type instead of throwing an unhelpful error.

    >>> key_tab.rename({0:'PolicyID'}, axis = 1)
ValueError('nyi')
    >>> key_tab.rename({0:'PolicyID'}, axis = 1)
pykx.KeyedTable(pykx.q('
idx| x y
---| ---
0  | 0 3
1  | 1 2
2  | 2 1
'))

  • Improved upon the quality of Table.rename() error messages and documentation on the function.

  • PyKX would error with _get_config_value() missing 1 required positional argument: 'default' on import if a license was not found since 2.3.0. Now correctly opens the license walkthrough.

  • Pandas 2.2.0 introduced breaking changes which effect PyKX. PyKX dependencies have been updated to pandas>=1.2, < 2.2.0 until these are resolved. Data casting behavior leads to an unexpected datatype being returned:

    >>> pd.Series([1, pd.NA, 3], dtype=pd.Int64Dtype()).to_numpy()
array([1, <NA>, 3], dtype=object)

>>> kx.K(pd.Series([1, pd.NA, 3], dtype=pd.Int64Dtype()))
pykx.LongVector(pykx.q('1 0N 3'))
    >>> pd.Series([1, pd.NA, 3], dtype=pd.Int64Dtype()).to_numpy()
array([ 1., nan,  3.])

>>> kx.K(pd.Series([1, pd.NA, 3], dtype=pd.Int64Dtype()))
pykx.FloatVector(pykx.q('1 -9.223372e+18 3'))

  • df.select_dtypes() updated to now accept kx.*Atom values for include/exclude params. Use of kx.CharVector will return error.

  • To align with other areas of PyKX the upsert and insert methods for PyKX tables and keyed tables now support the keyword argument inplace, this change will deprecate usage of replace_self with the next major release of PyKX.

Beta Features

  • Addition of the concept of Remote Function execution to PyKX, this allows users, from a Python session to define Python functions which will be executed on a remote q/kdb+ server running PyKX under q. The intention with this feature is to allow onboarding of Python first operations within existing or q/kdb+ first infrastructures

    >>> from pykx.remote import function, session
>>> remote_session = session()
>>> remote_session.create('localhost', 5050)
>>> @function(remote_session)
... def func(x):
...     return x+1
>>> func(2)            # Functionality run on q server
pykx.LongAtom(pykx.q('3'))
>>> remote_session.clear()

PyKX 2.3.0

Release Date

2024-01-22

Additions

  • PyKX now supports the use of KDB_LICENSE_B64 or KDB_K4LICENSE_B64 configuration values/environment variables to define the content of a kc.lic or k4.lic license respectively if no license is found on initial usage of PyKX.

  • Shortcut provided for access to current date, time and timestamp information using 'today' and 'now'.

    >>> kx.DateAtom('today')
pykx.DateAtom(pykx.q('2024.01.05'))
>>> kx.TimeAtom('now')
pykx.TimeAtom(pykx.q('16:15:32.724'))
>>> kx.TimestampAtom('now')
pykx.TimestampAtom(pykx.q('2024.01.05T16:15:42.926631000'))

  • Addition of support for inplace updates of PyKX tables modified using qsql select/update/delete operations on in-memory data. Application of inplace modifications is not supported for direct application on Partitioned/Splayed tables.

    >>> N = 1000
>>> qtab = kx.Table(data={'x': kx.random.random(N, 1.0, seed=10)})
>>> qtab
pykx.Table(pykx.q('
x
-----------
0.0891041
0.8345194
0.3621949
0.999934
0.3837986
..
'))
>>> kx.q.qsql.select(qtab, where = ['x>0.5'], inplace=True)
pykx.Table(pykx.q('
x
-----------
0.8345194
0.999934
0.8619188
0.7517286
0.6348263
..
'))
>>> qtab
pykx.Table(pykx.q('
x
-----------
0.8345194
0.999934
0.8619188
0.7517286
0.6348263
..
'))

  • Addition of reset_index, add_suffix, add_prefix, count, skew and std functionality to Pandas Like API

    • See here for details of supported keyword arguments, limitations and examples.
  • %%q Jupyter Notebook magic adds --debug option which prints the q backtrace if the cell execution fails.
  • Release 2.3.0 adds to PyKX the concept of Beta features, these features are available to users through setting the configuration/environment variable PYKX_BETA_FEATURES. For more information on Beta features see further documentation here

Fixes and Improvements

  • %%q Jupyter Notebook magic now returns all outputs up to and including an error when thrown. Previously only the error was returned.

  • %%q Jupyter Notebook magic ignores accidental whitespace in execution options. Below example no longer fails with Received unknown argument error:

    %%q   --port 5000

  • In cases where PyKX IPC sockets read data from unexpected publishers it could raise an IndexError. PyKX will now provide a more verbose error indicating that an unexpected message has been received, the bytes processed and requests a reproducible example to be provided if possible.

  • Update to table column retrieval logic to error when a user attempts to access a non-existent column with a queried table.

    >>> tab = kx.Table(data = {'a': [1, 2, 3]})
>>> tab['c']
pykx.LongVector(pykx.q('`long$()'))
    >>> tab = kx.Table(data = {'a': [1, 2, 3]})
>>> tab['c']
..
QError: Attempted to retrieve inaccessible column: c

  • Improved error message for conversion failures.

  • Fixes an issue where a user would receive a length error when attempting to apply min, max, prod and sum functions on pykx.KeyedTable objects.

Beta Features

  • Database Management functionality has been added for the creation, loading and maintenance of PyKX Partitioned Databases. A full worked example of this functionality can be found here along with full API documentation which includes examples of each function here. The API includes but is not limited to the following:

    • Database table creation and renaming.
      • Enumeration of in-memory tables against on-disk sym file.
    • Column listing, addition, reordering, renaming copying, function application and deletion on-disk.
    • Attribute setting and removal.
    • Addition of missing tables from partitions within a database.

  • Added PYKX_THREADING environment variable that allows multithreaded programs to modify state when calling into python on secondary threads. Note: This behaviour is only supported on Linux / MacOS.

    Note

    When using PYKX_THREADING you must ensure you call kx.shutdown_thread() at the end of the script to ensure the background thread is properly closed.

PyKX 2.2.3

Release Date

2024-01-11

Fixes and Improvements

  • PyKX now raises an error appropriately when failing to locate msvcr100.dll when loading on Windows.
  • Config values now default to False when not set rather than None.
  • Resolved issue where both PYKX_NO_SIGNAL and PYKX_NO_SIGINT needed to be set to take effect. Now correctly accepts either.
  • Reduced signal handling list to only SIGINT and SIGTERM. The inclusion of SIGSEGV since 2.2.1 could cause segfaults with compressed enum files.
  • Updated q libraries to 2024.01.09

Note

PyKX 2.2.3 is currently not available for Mac x86 for all Python versions, additionally it is unavailable for Mac ARM on Python 3.7. Updated builds will be provided once available.

PyKX 2.2.2

Warning

Please skip this release and use 2.2.3 or newer. This is due to potential segfaults when reading compressed files.

Release Date

2023-12-12

Fixes and Improvements

  • Conversions between UUID and pykx.GUID types could produce invalid results under various conditions in both licensed and unlicensed mode.
  • A regression in 2.2.1 resulted in SIGINT signals being incorrectly treated as SIGTERM style signals, PyKX now resets all signals overwritten by PyKX to their values prior to import.
  • Indexing regression in 2.2.1 causing hangs for certain inputs such as tbl[::-1] has been resolved.

PyKX 2.2.1

Warning

Please skip this release and use 2.2.3 or newer. This is due to potential segfaults when reading compressed files.

Release Date

2023-11-30

Fixes and Improvements

  • Some messages to stdout were not being captured when redirecting. Now all are captured.
  • Deprecation of internally used environment variable UNDER_PYTHON which has been replaced by PYKX_UNDER_PYTHON to align with other internally used environment variables.
  • Fix Unknown default conversion type error when PYKX_DEFAULT_CONVERSION is set to k
  • Numpy dependency for Python 3.11 corrected to numpy~=1.23.2
  • pykx.q.qsql.select and pykx.q.qsql.exec statements no longer use get calls for table retrieval unnecessarily when operating locally or via IPC.

  • Null integral values in table keys will no longer convert the underlying vectors to floats when converting from a pykx.KeyedTable to pandas.DataFrame

    >>> kx.q('`col1 xkey ([] col1: (1j; 2j; 0Nj); col2:(1j; 2j; 0Nj); col3:`a`b`c)').pd()
       col2 col3
col1
 1.0      1    a
 2.0      2    b
 0.0     --    c
    >>> kx.q('`col1 xkey ([] col1: (1j; 2j; 0Nj); col2:(1j; 2j; 0Nj); col3:`a`b`c)').pd()
       col2 col3
col1
 1       1    a
 2       2    b
--      --    c

    Warning

    For multi-keyed PyKX tables converted to Pandas the appropriate round-trip behaviour is supported however due to limitations in Pandas displaying of these as masked arrays is not supported as below

    >>> kx.q('`col1`col2 xkey ([] col1: (1j; 2j; 0Nj); col2:(1j; 2j; 0Nj); col3:`a`b`c)').pd()
                                          col3
col1                 col2
 1                    1                      a
 2                    2                      b
-9223372036854775808 -9223372036854775808    c

  • Fix to issue where providing SIGTERM signals to Python processes running PyKX would not result in the Python process being terminated.

  • Addition of deprecation warning for environmental configuration option PYKX_NO_SIGINT which is to be replaced by PYKX_NO_SIGNAL. This is used when users require no signal handling logic overwrites and now covers SIGTERM, SIGINT, SIGABRT signals amongst others.

  • Use of pykx.q.system.variables no longer prepends leading . to supplied string allowing users to get the variables associated with dictionary like namespaces.

    >>> kx.q('.test.a:1;.test.b:2')
>>> kx.q('test.c:3;test.d:4')
>>> kx.q.system.variables('.test')
pykx.SymbolVector(pykx.q('`s#`a`b'))
>>> kx.q.system.variables('test')
pykx.SymbolVector(pykx.q('`s#`a`b'))
    >>> kx.q('.test.a:1;.test.b:2')
>>> kx.q('test.c:3;test.d:4')
>>> kx.q.system.variables('.test')
pykx.SymbolVector(pykx.q('`s#`a`b'))
>>> kx.q.system.variables('test')
pykx.SymbolVector(pykx.q('`s#`c`d'))

  • q dictionaries with tables as keys were being incorrectly wrapped as pykx.KeyedTable. Now corrected to pykx.Dictionary:

    >>> type(pykx.q('([] a:1 2 3;b:2 3 4)!enlist each 1 2 3'))
<class 'pykx.wrappers.KeyedTable'>
    >>> type(pykx.q('([] a:1 2 3;b:2 3 4)!enlist each 1 2 3'))
<class 'pykx.wrappers.Dictionary'>
    • Added consistent conversion of datetime.time objects
    q).pykx.pyexec"from datetime import time"
q).pykx.eval["time(11, 34, 56)"]`
foreign
    >>> kx.toq(time(11, 34, 56))
Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
    File "pykx/toq.pyx", line 2641, in pykx.toq.ToqModule.__call__
    File "pykx/toq.pyx", line 270, in pykx.toq._default_converter
TypeError: Cannot convert <class 'datetime.time'> 'datetime.time(11, 34, 56)' to K object
    q).pykx.pyexec"from datetime import time"
q).pykx.eval["time(11, 34, 56)"]`
0D11:34:56.000000000
    >>> kx.toq(time(11, 34, 56))
pykx.TimespanAtom(pykx.q('0D11:34:56.000000000'))

  • Fixed null value for TimestampVector returning NoneType instead of pykx.wrappers.TimestampAtom for .py() method

    >>> for x in kx.q('0Np,.z.p').py():
...     print(type (x))
<class 'NoneType'>
<class 'datetime.datetime'>
    >>> for x in kx.q('0Np,.z.p').py():
...     print(type (x))
<class 'pykx.wrappers.TimestampAtom'>
<class 'datetime.datetime'>

Upgrade considerations

  • If dependent on the environment variable UNDER_PYTHON please upgrade your code to use PYKX_UNDER_PYTHON

PyKX 2.2.0

Release Date

2023-11-09

Additions

  • Addition of agg method for application of aggregation functions on pykx.Table and pykx.GroupbyTable objects

    >>> import pykx as kx
>>> import numpy as np
>>> import statistics
    >>> def mode(x):
...     return statistics.mode(x)
>>> tab = kx.Table(data={
...     'x': kx.random.random(1000, 10),
...     'x1': kx.random.random(1000, 10.0)})
>>> tab.agg(mode)
pykx.Dictionary(pykx.q('
x | 6
x1| 2.294631
'))
>>> tab.agg(['min', 'mean'])
pykx.KeyedTable(pykx.q('
function| x     x1
--------| -----------------
min     | 0     0.009771725
mean    | 4.588 5.152194
'))
>>>
>>> group_tab = kx.Table(data={
...     'x': kx.random.random(1000, ['a', 'b']),
...     'y': kx.random.random(1000, 10.0)})
>>> group_tab.groupby('x').agg('mean')
pykx.KeyedTable(pykx.q('
x| y
-| --------
a| 5.239048
b| 4.885599
'))
>>> group_tab.groupby('x').agg(mode)
pykx.KeyedTable(pykx.q('
x| y
-| --------
a| 1.870281
b| 4.46898
'))

  • Addition of the ability for users to run min, max, mean, median, sum and mode methods on vector objects within PyKX.

    >>> import pykx as kx
>>> random_vec = kx.random.random(5, 3, seed=20)
pykx.LongVector(pykx.q('0 1 0 1 1'))
>>> random_vec.mode()
pykx.LongVector(pykx.q(',1'))
>>> random_vec.mean()
pykx.FloatAtom(pykx.q('0.6'))

  • Addition of the ability for users to assign objects to pykx.*Vector and pykx.List objects

    >>> import pykx as kx
>>> qvec = kx.q.til(10)
>>> qvec
pykx.LongVector(pykx.q('0 1 2 3 4 5 6 7 8 9'))
>>> qvec[3] = 45
>>> qvec
pykx.LongVector(pykx.q('0 1 2 45 4 5 6 7 8 9'))
>>> qvec[-1] = 20
>>> qvec
pykx.LongVector(pykx.q('0 1 2 45 4 5 6 7 8 20'))

  • Users can now assign/update keys of a pykx.Dictionary object using an in-built __setitem__ method as follows

    >>> import pykx as kx
>>> pykx_dict = kx.toq({'x': 1})
>>> pykx_dict
pykx.Dictionary(pykx.q('x| 1'))
>>> pykx_dict['x1'] = 2
>>> pykx_dict
pykx.Dictionary(pykx.q('
x | 1
x1| 2
'))
>>> for i in range(3):
...     pykx_dict['x']+=i
...
>>> pykx_dict
pykx.Dictionary(pykx.q('
x | 4
x1| 2
'))

  • Addition of null and inf properties for pykx.Atom objects allowing for Pythonic retrieval of nulls and infinities

    >>> import pykx as kx
>>> kx.FloatAtom.null
pykx.FloatAtom(pykx.q('0n'))
>>> kx.GUIDAtom.null
pykx.GUIDAtom(pykx.q('00000000-0000-0000-0000-000000000000'))
>>> kx.IntAtom.inf
pykx.IntAtom(pykx.q('0Wi'))
>>> -kx.IntAtom.inf
pykx.IntAtom(pykx.q('-0Wi'))

  • Users can now use the environment variables PYKX_UNLICENSED="true" or PYKX_LICENSED="true" set this as part of configuration within their .pykx-config file to allow unlicensed or licensed mode to be the default behaviour on initialisation for example:

    >>> import os
>>> os.environ['PYKX_UNLICESED'] = "true"
>>> import pykx as kx
>>> kx.toq([1, 2, 3])
pykx.List._from_addr(0x7fee46000a00)

  • Addition of append and extend methods to pykx.*Vector and pykx.List objects

    >>> import pykx as kx
>>> qvec = kx.q.til(5)
>>> qvec.append(100)
>>> qvec
pykx.LongVector(pykx.q('0 1 2 3 4 100'))
>>> qvec.extend([1, 2, 3])
>>> qvec
pykx.LongVector(pykx.q('0 1 2 3 4 100 1 2 3'))

  • Addition of debug keyword argument to the __call__ method on EmbeddedQ and QConnection objects to provide backtraces on q code.

    >>> import pykx as kx
>>> kx.q('{[x] a: 5; b: til a; c: til x; b,c}', b'foo', debug=True)
backtrace:
  [3]  (.q.til)

  [2]  {[x] a: 5; b: til a; c: til x; b,c}
                               ^
  [1]  (.Q.trp)

      [0]  {[pykxquery] .Q.trp[value; pykxquery; {2@"backtrace:
                    ^
",.Q.sbt y;'x}]}
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "...\site-packages\pykx\embedded_q.py", line 226, in __call__
    return factory(result, False)
  File "pykx\\_wrappers.pyx", line 504, in pykx._wrappers._factory
  File "pykx\\_wrappers.pyx", line 497, in pykx._wrappers.factory
pykx.exceptions.QError: type

  • Added feature to extract individual elements of both TimestampAtom and TimestampVector in a pythonic way including:

    • date - DateAtom / DateVector
    • time - TimeAtom / TimeVector
    • year - IntAtom / IntVector
    • month - IntAtom / IntVector
    • day - IntAtom / IntVector
    • hour - IntAtom / IntVector
    • minute - IntAtom / IntVector
    • second - IntAtom / IntVector
    >>> timestamp_atom = kx.q('2023.10.25D16:42:01.292070013')

>>> timestamp_atom.time
pykx.TimeAtom(pykx.q('16:42:01.292'))
>>> timestamp_atom.date
pykx.DateAtom(pykx.q('2023.10.25'))
>>> timestamp_atom.minute
pykx.IntAtom(pykx.q('42i'))

>>> timestamp_atom_2 = kx.q('2018.11.09D12:21:08.456123789')
>>> timestamp_vector = kx.q('enlist', timestamp_atom, timestamp_atom_2)

>>> timestamp_vector.time
pykx.TimeVector(pykx.q('16:42:01.292 12:21:08.456'))
>>> timestamp_vector.date
pykx.DateVector(pykx.q('2023.10.25 2018.11.09'))
>>> timestamp_vector.hour
pykx.IntVector(pykx.q('16 12i'))

  • Addition of poll_recv_async to RawQConnection objects to support asynchronous polling.

  • Addition of negative slicing to list , vector and table objects

    ```python
>>> import pykx as kx
>>> qlist = kx.q('("a";2;3.3;`four)')
>>> qlist[-3:]
pykx.List(pykx.q('
2
3.3
`four
'))

>>> vector = kx.q('til 5')
>>> vector[:-1]
pykx.LongVector(pykx.q('0 1 2 3'))

>>> table = kx.q('([] a:1 2 3; b:4 5 6; c:7 8 9)')
>>> table[-2:]
pykx.Table(pykx.q('
a b c
-----
2 5 8
3 6 9
'))
```

Fixes and Improvements

  • Fix to allow users to use Python functions when operating on a pykx.GroupbyTable with an apply function

    >>> import pykx as kx
>>> import statistics
>>> def mode(x):
...    return statistics.mode(x)
>>> tab = kx.q('([]sym:`a`b`a`a;1 1 0 0)')
>>> tab.groupby('sym').apply(mode)
pykx.KeyedTable(pykx.q('
sym| x
---| -
a  | 0
b  | 1
'))

  • Added debug dependency for find-libpython that can be installed using pip install "pykx[debug]". This dependency can be used to help find libpython in the scenario that pykx.q fails to find it.

  • Usage of the QARGS to enable/disable various elements of kdb Insights functionality has been formalised, outlined here. For example users can now use QARGS="--no-objstor" to disable object storage capabilities.

  • Failure to initialise PyKX with exp or embedq license errors will now prompt users to ask if they wish to download an appropriate license following expiry or use of an invalid license

    Your PyKX license has now expired.

Captured output from initialization attempt:
    '2023.10.18T13:27:59.719 licence error: exp

Would you like to renew your license? [Y/n]:
    You appear to be using a non kdb Insights license.

Captured output from initialization attempt:
    '2023.10.18T13:27:59.719 licence error: embedq

Running PyKX in the absence of a kdb Insights license has reduced functionality.
Would you like to install a kdb Insights personal license? [Y/n]:
    Your installed license is out of date for this version of PyKX and must be updated.

Captured output from initialization attempt:
    '2023.10.18T13:27:59.719 licence error: upd

Would you like to install an updated kdb Insights personal license? [Y/n]:

  • PyKX sets PYKX_EXECUTABLE to use when loading embedded q to prevent errors if launched using a different Python executable than that which will be found in PATH

  • Jupyter Notebook:

    • Removal of FutureWarning when displaying tables and dictionaries.
    • Revert issue causing results to be displayed as pointer references rather than Python objects in unlicensed mode.
    • %%q magic now suppresses displaying of ::.
    • %%q magic addition of --display option to have display be called on returned items in place of the default print.

  • PyKXReimport now additionally unsets/resets: PYKX_SKIP_UNDERQ, PYKX_EXECUTABLE, PYKX_DIR

  • When attempting to deserialize unsupported byte representations pykx.deserialize would result in a segmentation fault, this has been updated such that an error message is now raised.

    >>> import pykx as kx
>>> kx.deserialize(b'invalid byte string')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/anaconda3/lib/python3.8/site-packages/pykx/serialize.py", line 123, in deserialize
    return _deserialize(data)
  File "pykx/_wrappers.pyx", line 131, in pykx._wrappers.deserialize
  File "pykx/_wrappers.pyx", line 135, in pykx._wrappers.deserialize
pykx.exceptions.QError: Failed to deserialize supplied non PyKX IPC serialized format object

  • Fixed an issue when using multiple asynchronous QConnection connected to multiple servers.

  • Users can now access the length of and index into pykx.CharAtom objects to align with Pythonic equivalent data

    >>> qatom = kx.CharAtom('a')
>>> len(qatom)
1
>>> qatom[0]
pykx.CharAtom(pykx.q('"a"'))

PyKX 2.1.2

Release Date

2023-10-24

Fixes and Improvements

  • Fix to issue where functions retrieved using the Context Interface with names update/delete/select/exec would result in an AttributeError

    >>> import pykx as kx
>>> kx.q.test
<pykx.ctx.QContext of .test with [ctx]>
>>> kx.q.test.ctx.update(1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/anaconda3/lib/python3.8/site-packages/pykx/ctx.py", line 121, in __getattr__
    raise AttributeError(f'{key}: {self._unsupported_keys_with_msg[key]}')
AttributeError: update: Usage of 'update' function directly via 'q' context not supported, please consider using 'pykx.q.qsql.update'
    >>> import pykx as kx
>>> kx.q.test
<pykx.ctx.QContext of .test with [ctx]>
>>> kx.q.test.ctx.update(1)
pykx.LongAtom(pykx.q('2'))

PyKX 2.1.1

Release Date

2023-10-10

Fixes and Improvements

  • Fix to regression in PyKX 2.1.0 where execution of from pykx import * would result in the following behaviour

    >>> from pykx import *
...
AttributeError: module 'pykx' has no attribute 'PyKXSerialized'

PyKX 2.1.0

Release Date

2023-10-09

Additions

  • Added functionality to the CSV Reader to allow for the input of data structures while defining column types. For example, the following reads a CSV file and specifies the types of the three columns named x1, x2 and x3 to be of type Integer, GUID and Timestamp.

    >>> table = q.read.csv('example.csv', {'x1':kx.IntAtom,'x2':kx.GUIDAtom,'x3':kx.TimestampAtom})

  • Conversions from Pandas Dataframes and PyArrow tables using pykx.toq can now specify the ktype argument as a dictionary allowing selective type conversions for defined columns

    >>> import pykx as kx
>>> import pandas as pd
>>> df = pd.DataFrame.from_dict({'x': [1, 2], 'y': ['a', 'b']})
>>> kx.toq(df).dtypes
pykx.Table(pykx.q('
columns type
-----------------------
x       "kx.LongAtom"
y       "kx.SymbolAtom"
'))
>>> kx.toq(df, ktype={'x': kx.FloatAtom}).dtypes
pykx.Table(pykx.q('
columns type
-----------------------
x       "kx.FloatAtom"
y       "kx.SymbolAtom"
'))

  • Addition of the ability for users to run an apply method on vector objects within PyKX allowing the application of Python/PyKX functionality on these vectors directly

    >>> import pykx as kx
>>> random_vec = kx.random.random(2, 10.0, seed=100)
>>> random_vec
pykx.FloatVector(pykx.q('8.909647 3.451941'))
>>> random_vec.apply(lambda x:x+1)
pykx.FloatVector(pykx.q('9.909647 4.451941'))
>>> def func(x, y):
...     return x+y
>>> random_vec.apply(func, y=2)
pykx.FloatVector(pykx.q('10.909647 5.451941'))

  • Notebooks will HTML print tables and dictionaries through the addition of _repr_html_. Previous q style output is still available using print.

  • Added serialize and deserialize as base methods to assist with the serialization of K objects for manual use over IPC.
  • Added support for pandas version 2.0.

Pandas 2.0 has deprecated the datetime64[D/M] types.

Due to this change it is not always possible to determine if the resulting q Table should use a MonthVector or a DayVector. In the scenario that it is not possible to determine the expected type a warning will be raised and the DayVector type will be used as a default.

Fixes and Improvements

  • Empty PyKX keyed tables can now be converted to Pandas DataFrames, previously this would raise a ValueError

    >>> import pykx as kx
>>> df = kx.q('0#`a xkey ([]a:1 2 3;b:3 4 5)').pd()
>>> df
Empty DataFrame
Columns: [b]
Index: []
>>> df.index.name
'a'
>>> kx.toq(df)
pykx.KeyedTable(pykx.q('
a| b
-| -
'))

  • Fix to issue introduced in 2.0.0 where indexing of pykx.Table returned incorrect values when passed negative/out of range values

    >>> import pykx as kx
>>> tab = kx.Table(data={"c1": list(range(3))})
>>> tbl[-1]
pykx.Table(pykx.q('
c1
--

'))
>>> tab[-4]
pykx.Table(pykx.q('
c1
--

'))
>>> tab[3]
pykx.Table(pykx.q('
c1
--

'))
    >>> import pykx as kx
>>> tab = kx.Table(data={"c1": list(range(3))})
>>> tab[-1]
pykx.Table(pykx.q('
c1
--
2
'))
>>> tab[-4]
...
IndexError: index out of range
>>> tab[3]
...
IndexError: index out of range

  • Fix to issue where PyKX would not initialize when users with a QINIT environment variable set which pointed to a file contained a show statement

  • Retrieval of dtypes with tables containing real columns will now return kx.RealAtom for the type rather than incorrectly returning kx.ShortAtom
  • Users with QINIT environment variable would previously load twice on initialization within PyKX
  • Users installing PyKX under q on Windows had been missing installation of required files using pykx.install_into_QHOME()

Dependency Updates

  • The version of Cython used to build PyKX was updated to the full 3.0.x release version.

PyKX 2.0.1

Release Date

2023-09-21

Fixes and Improvements

  • User input based license initialization introduced in 2.0.0 no longer expects user input when operating in a non-interactive modality, use of PyKX in this mode will revert to previous behavior
  • Use of the environment variables QARGS='--unlicensed' or QARGS='--licensed' operate correctly following regression in 2.0.0
  • Fix to issue where OSError would be raised when close() was called on an IPC connection which has already disconnected server side

PyKX 2.0.0

Release Date

2023-09-18

  • PyKX 2.0.0 major version increase is required due to the following major changes which are likely to constitute breaking changes
    • Pandas API functionality is enabled permanently which will modify data indexing and retrieval of pykx.Table objects. Users should ensure to review and test their codebase before upgrading.
    • EmbedPy replacement functionality for PyKX under q is now non-beta for Linux and MacOS installations, see here for full information on 2.0.0 changelog.

Additions

  • Pandas API is enabled by default allowing users to treat PyKX Tables similarly to Pandas Dataframes for a limited subset of Pandas like functionality. As a result of this change the environment variable PYKX_ENABLE_PANDAS_API is no longer required.
  • Addition of file based configuration setting allowing users to define profiles for various PyKX modalities through definition of the file .pykx.config see here for more information.
  • Addition of new PyKX license installation workflow for users who do not have a PyKX license allowing for installation of personal licenses via a form based install process. This updated flow is outlined here.

  • Addition of a new module pykx.license which provides functionality for the installation of licenses, checking of days to expiry and validation that the license which PyKX is using matches the file/base64 string the user expects. For more information see here.

  • Addition of apply and groupby methods to PyKX Tables allowing users to perform additional advanced analytics for example:

    >>> import pykx as kx
>>> N = 1000000
>>> tab = kx.Table(data = {
...       'price': kx.random.random(N, 10.0),
...       'sym': kx.random.random(N, ['a', 'b', 'c'])
...       })
>>> tab.groupby('sym').apply(kx.q.sum)
pykx.KeyedTable(pykx.q('
sym| price
---| --------
a  | 166759.4
b  | 166963.6
c  | 166444.1
'))

  • Addition of a new module pykx.random which provides functionality for the generation of random data and setting of random seeds. For more information see here

    >>> import pykx as kx
>>> kx.random.random(5, 1.0, seed=123)
pykx.FloatVector(pykx.q('0.1959057 0.06460555 0.9550039 0.4991214 0.3207941'))
>>> kx.random.seed(123)
>>> kx.random.random(5, 1.0)
pykx.FloatVector(pykx.q('0.1959057 0.06460555 0.9550039 0.4991214 0.3207941'))
>>> kx.random.random([3, 4], ['a', 'b', 'c'])
pykx.List(pykx.q('
b c a b
b a b a
a a a a
'))

  • Addition of a new module pykx.register which provides functionality for the addition of user specified type conversions for Python objects to q via the function py_toq for more information see here. The following is an example of using this function

    >>> import pykx as kx
>>> def complex_conversion(data):
...     return kx.q([data.real, data.imag])
>>> kx.register.py_toq(complex, complex_conversion)
>>> kx.toq(complex(1, 2))
pykx.FloatVector(pykx.q('1 2f'))

  • Support for fixed length string dtype with Numpy arrays

    >>> import pykx as kx
>>> import numpy as np
>>> kx.toq(np.array([b'string', b'test'], dtype='|S7'))
pykx.List(pykx.q('
"string"
"test"
'))

Fixes and Improvements

  • Update to environment variable definitions in all cases to be prefixed with PYKX_*
  • Return of Pandas API functions dtypes, columns, empty, ndim, size and shape return kx objects rather than Pythonic objects
  • Removed GLIBC_2.34 dependency for conda installs
  • Removed the ability for users to incorrectly call pykx.q.{select/exec/update/delete} with error message now suggesting usage of pykx.q.qsql.{function}
  • Fixed behavior of loc when used on KeyedTable objects to match the pandas behavior.
  • Addition of warning on failure to link the content of a users QHOME directory pointing users to documentation for warning suppression
  • Update to PyKX foreign function handling to support application of Path objects as first argument i.e. q("{[f;x] f x}")(lambda x: x)(Path('test'))
  • SQL interface will attempt to automatically load on Windows and Mac
  • Attempts to serialize pykx.Foreign, pykx.SplayedTable and pykx.PartitionedTable objects will now result in a type error fixing a previous issue where this could result in a segmentation fault.
  • Messages mistakenly sent to a PyKX client handle are now gracefully ignored.

  • Application of Pandas API dtypes operations return a table containing column to type mappings with PyKX object specific types rather than Pandas/Python types

    >>> table = kx.Table([[1, 'a', 2.0, b'testing', b'b'], [2, 'b', 3.0, b'test', b'a']])
>>> print(table)
x x1 x2 x3        x4
--------------------
1 a  2  "testing" b
2 b  3  "test"    a
>>> table.dtypes
x       int64
x1     object
x2    float64
x3     object
x4        |S1
dtype: object
    >>> table = kx.Table([[1, 'a', 2.0, b'testing', b'b'], [2, 'b', 3.0, b'test', b'a']])
>>> print(table)
x x1 x2 x3        x4
--------------------
1 a  2  "testing" b
2 b  3  "test"    a
>>> table.dtypes
pykx.Table(pykx.q('
columns type
-----------------------
x       "kx.LongAtom"
x1      "kx.SymbolAtom"
x2      "kx.FloatAtom"
x3      "kx.CharVector"
x4      "kx.CharAtom"
'))

  • Fixed an issue where inequality checks would return False incorrectly

    >>> import pykx as kx
>>> kx.q('5') != None
pykx.q('0b')
    >>> import pykx as kx
>>> kx.q('5') != None
pykx.q('1b')

Breaking Changes

  • Pandas API functionality is enabled permanently which will modify data indexing and retrieval. Users should ensure to review and test their codebase before upgrading.

PyKX 1.6.3

Release Date

2023-08-18

Additions

  • Addition of argument return_info to pykx.util.debug_environment allowing user to optionally return the result as a str rather than to stdout

Fixes and Improvements

  • Fixed Pandas API use of ndim functionality which should return 2 when interacting with tables following the expected Pandas behavior.
  • Fixed an error when using the Pandas API to update a column with a Symbols, Characters, and Generic Lists.
  • Prevent attempting to pass wrapped Python functions over IPC.
  • Support IPC payloads over 4GiB.

PyKX 1.6.2

Release Date

2023-08-15

Additions

  • Added to_local_folder kwarg to install_into_QHOME to enable use of pykx.q without write access to QHOME.
  • Added an example that shows how to use EmbeddedQ in a multithreaded context where the threads need to modify global state.
  • Added PYKX_NO_SIGINT environment variable.

Fixes and Improvements

  • Fixed an issue causing a crash when closing QConnection instances on Windows.
  • Updated q 4.0 libraries to 2023.08.11. Note: Mac ARM release remains on 2022.09.30.
  • Fix Jupyter Magic in local mode.
  • Fix error when binding with FFI in QINIT.
  • Fix issue calling peach with PYKX_RELEASE_GIL set to true when calling a Python function.

PyKX 1.6.1

Release Date

2023-07-19

Additions

  • Added sorted, grouped, parted, and unique. As methods off of Tables and Vectors.
  • Added PyKXReimport class to allow subprocesses to reimport PyKX safely.
    • Also includes .pykx.safeReimport in pykx.q to allows this behavior when running under q as well.
  • Added environment variables to specify a path to libpython in the case pykx.q cannot find it.

Fixes and Improvements

  • Fixed memory leaks within the various QConnection subclasses.
  • Added deprecation warning around the discontinuing of support for Python 3.7.
  • Fixed bug in Jupyter Notebook magic command.
  • Fixed a bug causing np.ndarray's to not work within ufuncs.
  • Fixed a memory leak within all QConnection subclasses. Fixed for both PyKX as a client and as a server.
  • Updated insights libraries to 4.0.2
  • Fixed pykx.q functionality when run on Windows.
  • Fixed an issue where reimporting PyKX when run under q would cause a segmentation fault.
  • Updated the warning message for the insights core libraries failing to load to make it more clear that no error has occurred.

PyKX 1.6.0

Release Date

2023-06-16

Additions

  • Added merge_asof to the Pandas like API.
    • See here for details of supported keyword arguments and limitations.
  • Added set_index to the Pandas like API.
    • See here for details of supported keyword arguments and limitations.
  • Added a set of basic computation methods operating on tabular data to the Pandas like API. See here for available methods and examples.
  • pykx.util.debug_environment added to help with import errors.
  • q vector type promotion in licensed mode.
  • Added .pykx.toraw to pykx.q to enable raw conversions (e.g. kx.toq(x, raw=True))
  • Added support for Python 3.11.
    • Support for PyArrow in this python version is currently in Beta.
  • Added the ability to use kx.RawQConnection as a Python based q server using kx.RawQConnection(port=x, as_server=True).
    • More documentation around using this functionality can be found here.

Fixes and Improvements

  • Improved error on Windows if msvcr100.dll is not found
  • Updated q libraries to 2023.04.17
  • Fixed an issue that caused q functions that shared a name with python key words to be inaccessible using the context interface.
    • It is now possible to access any q function that uses a python keyword as its name by adding an underscore to the name (e.g. except can now be accessed using q.except_).
  • Fixed an issue with .pykx.get and .pykx.getattr not raising errors correctly.
  • Fixed an issue where deserializing data would sometimes not error correctly.

  • Users can now add new column(s) to an in-memory table using assignment when using the Pandas like API.

    >>> import os
>>> os.environ['PYKX_ENABLE_PANDAS_API'] = 'true'
>>> import pykx as kx
>>> import numpy as np
>>> tab = kx.q('([]100?1f;100?1f)')
>>> tab['x2'] = np.arange(0, 100)
>>> tab
pykx.Table(pykx.q('
x           x1         x2
-------------------------
0.1485357   0.1780839  0
0.4857547   0.3017723  1
0.7123602   0.785033   2
0.3839461   0.5347096  3
0.3407215   0.7111716  4
0.05400102  0.411597   5
..
'))

PyKX 1.5.3

Release Date

2023-05-18

Additions

  • Added support for Pandas Float64Index.
  • Wheels for ARM64 based Macs are now available for download.

PyKX 1.5.2

Release Date

2023-04-30

Additions

  • Added support for ARM 64 Linux.

PyKX 1.5.1

Release Date

2023-04-28

Fixes and Improvements

  • Fixed an issue with pykx.q that caused errors to not be raised properly under q.
  • Fixed an issue when using .pykx.get and .pykx.getattr that caused multiple calls to be made.

PyKX 1.5.0

Release Date

2023-04-17

Additions

  • Added wrappers around various q system commands.
  • Added merge method to tables when using the Pandas API.
  • Added mean/median/mode functions to tables when using the Pandas API.
  • Added various functions around type conversions on tables when using the Pandas API.

Fixes and Improvements

  • Fix to allow GUIDs to be sent over IPC.
  • Fix an issue related to IPC connection using compression.
  • Improved the logic behind loading pykx.q under a q process allowing it to run on MacOS and Linux in any environment that EmbedPy works in.
  • Fix an issue that cause the default handler for SIGINT to be overwritten.
  • pykx.toq.from_callable returns a pykx.Composition rather than pykx.Lambda. When executed returns an unwrapped q object.
  • Fixed conversion of Pandas Timestamp objects.
  • Fixed an issue around the PyKX q magic command failing to load properly.
  • Fixed a bug around conversions of Pandas tables with no column names.
  • Fixed an issue around .pykx.qeval not returning unwrapped results in certain scenarios.

PyKX 1.4.2

Release Date

2023-03-08

Fixes and Improvements

  • Fixed an issue that would cause EmbeddedQ to fail to load.

PyKX 1.4.1

Release Date

2023-03-06

Fixes and Improvements

  • Added constructors for Table and KeyedTable objects to allow creation of these objects from dictionaries and list like objects.
  • Fixed a memory leak around calling wrapped Foreign objects in pykx.q.
  • Fixed an issue around the tls keyword argument when creating QConnection instances, as well as a bug in the unlicensed behavior of SecureQConnection's.

PyKX 1.4.0

Release Date

2023-01-23

Additions

  • Addition of a utility function kx.ssl_info() to retrieve the SSL configuration when running in unlicensed mode (returns the same info as kx.q('-26!0') with a license).
  • Addition of a utility function kx.schema.builder to allow for the generation of pykx.Table and pykx.KeyedTable types with a defined schema and zero rows, this provides an alternative to writing q code to create an empty table.
  • Added helper functions for inserting and upserting to k.Table instances. These functions provide new keyword arguments to run a test insert against the table or to enforce that the schema of the new row matches the existing table.
  • Added environment variable PYKX_NOQCE=1 to skip the loading of q Cloud Edition in order to speed up the import of PyKX.
  • Added environment variable PYKX_LOAD_PYARROW_UNSAFE=1 to import PyArrow without the "subprocess safety net" which is here to prevent some hard crashes (but is slower than a simple import).
  • Addition of method file_execute to kx.QConnection objects which allows the execution of a local .q script on a server instance as outlined here.
  • Added kx.RawQConnection which extends kx.AsyncQConnection with extra functions that allow a user to directly poll the send and receive selectors.
  • Added environment variable PYKX_RELEASE_GIL=1 to drop the Python GIL on calls into embedded q.
  • Added environment variable PYKX_Q_LOCK=1 to enable a Mutex Lock around calls into q, setting this environment variable to a number greater than 0 will set the max length in time to block before raising an error, a value of '-1' will block indefinitely and will not error, any other value will cause an error to be raised immediately if the lock cannot be acquired.
  • Added insert and upsert methods to Table and KeyedTable objects.

Fixes and Improvements

  • Fixed has_nulls and has_infs properties for subclasses of k.Collection.
  • Improved error output of kx.QConnection objects when an error is raised within the context interface.
  • Fixed .py() conversion of nested k.Dictionary objects and keyed k.Dictionary objects.
  • Fixed unclear error message when querying a QConnection instance that has been closed.
  • Added support for conversions of non C contiguous Numpy arrays.
  • Fixed conversion of null GUIDAtom's to and from Numpy types.
  • Improved performance of converting q enums to pandas Categoricals.

Beta Features

  • Added support for a Pandas like API around Table and KeyedTable instances, documentation for the specific functionality can be found here.
  • Added .pykx.setdefault to pykx.q which allows the default conversion type to be set without using environment variables.

PyKX 1.3.2

Release Date

2023-01-06

Features and Fixes

  • Fixed support for using TLS with SyncQConnection instances.

PyKX 1.3.1

Release Date

2022-11-16

Features and Fixes

  • Added environment variable PYKX_Q_LIB_LOCATION to specify a path to load the PyKX q libraries from.
    • Required files in this directory
      • If you are using the kdb+/q Insights core libraries they all must be present within this folder.
      • The read.q, write.q, and csvutil.q libraries that are bundled with PyKX.
      • A q.k that matches the version of q you are loading.
      • There must also be a subfolder (l64 / m64 / w64) based on the platform you are using.
        • Within this subfolder a copy of these files must also be present.
          • libq.(so / dylib) / q.dll.
          • libe.(so / dylib) / e.dll.
          • If using the Insights core libraries their respective shared objects must also be present here.
  • Updated core q libraries
    • PyKX now supports M1 Macs
    • OpenSSLv3 support
  • Added ability to specify maximum length for IPC error messages. The default is 256 characters and this can be changed by setting the PYKX_MAX_ERROR_LENGTH environment variable.

PyKX 1.3.0

Release Date

2022-10-20

Features and Fixes

  • Support for converting datetime.datetime objects with time zone information into pykx.TimestampAtoms and pykx.TimestampVectors.
  • Added a magic command to run cells of q code in a Jupyter Notebook. The addition of %%q at the start of a Jupyter Notebook cell will allow a user to execute q code locally similarly to loading a q file.
  • Added no_ctx key word argument to pykx.QConnection instances to disable sending extra queries to/from q to manage the context interface.
  • Improvements to SQL interface for PyKX including the addition of support for prepared statements, execution of these statements and retrieval of inputs see here for more information.
  • Fix to memory leak seen when converting Pandas Dataframes to q tables.
  • Removed unnecessary copy when sending q objects over IPC.

Beta Features

  • EmbedPy replacement functionality pykx.q updated significantly to provide parity with embedPy from a syntax perspective. Documentation of the interface here provides API usage. Note that initialization requires the first version of Python to be retrieved on a users PATH to have PyKX installed. Additional flexibility with respect to installation location is expected in 1.4.0 please provide any feedback to pykx@kx.com

PyKX 1.2.2

Release Date

2022-10-01

Features and Fixes

  • Fixed an issue causing the timeout argument for QConnection instances to not work properly.

PyKX 1.2.1

Release Date

2022-09-27

Features and Fixes

  • Added support for OpenSSLv3 for IPC connections created when in 'licensed' mode.
  • Updated conversion functionality for timestamps to support conversions within Pandas 1.5.0

PyKX 1.2.0

Release Date

2022-09-01

Features and Fixes

  • Support for converting any python type to a q Foreign object has been added.
  • Support for converting Pandas categorical types into pykx.EnumVector type objects.
  • Support for q querying against Pandas/PyArrow tables through internal conversion to q representation and subsequent query. kx.q.qsql.select(<pd.DataFrame>)
  • Support for casting Python objects prior to converting into K objects. (e.g. kx.IntAtom(3.14, cast=True) or kx.toq("3.14", ktype=kx.FloatAtom, cast=True)).
  • Support usage of Numpy __array_ufunc__'s directly on pykx.Vector types.
  • Support usage of Numpy __array_function__'s directly on pykx.Vector types (Note: these will return a Numpy ndarray object not an analogous pykx.K object).
  • Improved performance of pykx.SymbolVector conversion into native Python type (e.g. .py() conversion for pykx.SymbolVector's).
  • Improved performance and memory usage of various comparison operators between K types.
  • Improved performance of various pykx.toq conversions.
  • pykx.Vector types will now automatically enlist atomic types instead of erroring.
  • Fixed conversions of Numpy float types into pykx.FloatAtom and pykx.RealAtom types.
  • Fixed conversion of None Python objects into analogous null K types if a ktype is specified.
  • Added event_loop parameter to pykx.AsyncQConnection that takes a running event loop as a parameter and allows the event loop to manage pykx.QFuture objects.

Beta Features

  • Added extra functionality to pykx.q related to the calling and use of python foreign objects directly within a q process.
  • Support for NEP-49, which allows Numpy arrays to be converted into q Vectors without copying the underlying data. This behavior is opt-in and you can do so by setting the environment variable PYKX_ALLOCATOR to 1, "1" or True or by adding the flag --pykxalloc to the QARGS environment variable. Note: This feature also requires a python version of at least 3.8.
  • Support the ability to trigger early garbage collection of objects in the q memory space by adding --pykxgc to the QARGS environment variable, or by setting the PYKX_GC environment variable to 1, "1" or True.

PyKX 1.1.1

Release Date

2022-06-13

Features & Fixes

  • Added ability to skip symlinking $QHOME to PyKX's local $QHOME by setting the environment variable IGNORE_QHOME.

PyKX 1.1.0

Release Date

2022-06-07

Dependencies

  • The dependency on the system library libcurl has been made optional for Linux. If it is missing on Linux, a warning will be emitted instead of an error being raised, and the KX Insights Core library kurl will not be fully loaded. Windows and macOS are unaffected, as they don't support the KX Insights Core features to begin with.

Features & Fixes

  • Splayed and partitioned tables no longer emit warnings when instantiated.
  • Added pykx.Q.sql, which is a wrapper around KXI Core SQL.
  • .pykx.pyexec and .pykx.pyeval no longer segfault when called with a character atom.
  • Updated several pykx.toq tests so that they would not randomly fail.
  • Fixed error when pickling pykx.util.BlockManager in certain esoteric situations.
  • Fixed pandas.MultiIndex objects created by PyKX having pykx.SymbolAtom objects within them - now they have str objects instead, as they normally would.
  • Upgraded the included KX Insights Core libraries to version 3.0.0.
  • Added pykx.toq.from_datetime_date, which converts datetime.date objects into any q temporal atom that can represent a date (defaulting to a date atom).
  • Fixed error when user specifies -s or -q in $QARGS.
  • Fixed recursion error when accessing a non-existent attribute of pykx.q while in unlicensed mode. Now an attribute error is raised instead.
  • Fixed build error introduced by new rules enforced by new versions of setuptools.
  • Added pykx.Anymap.
  • Fixed support for kx.lic licenses.
  • The KXIC libraries are now loaded after q has been fully initialized, rather than during the initialization. This significantly reduces the time it takes to import PyKX.
  • PyKX now uses a single location for $QHOME: its lib directory within the installed package. The top-level contents of the $QHOME directory (prior to PyKX updating the env var when embedded q is initialized) will be symlinked into PyKX's lib directory, along with the content of any subdirectories under lib (e.g. l64, m64, w64). This enables loading scripts and libraries located in the original $QHOME directory during q initialization.
  • Improved performance (both execution speed and memory usage) of calling np.array on pykx.Vector instances. The best practice is still to use the np method instead of calling np.array on the pykx.Vector instance.
  • pykx.Vector is now a subclass of collections.abc.Sequence.
  • pykx.Mapping is not a subclass of collections.abc.Mapping.
  • Split pykx.QConnection into pykx.SyncQConnection and pykx.AsyncQConnection and added support for asynchronous IPC with q using async/await. Refer to the pykx.AsyncQConnection docs for more details.
  • Pandas dataframes containing Pandas extension arrays not originally created as Numpy arrays would result in errors when attempting to convert to q. For example a Dataframe with index of type pandas.MultiIndex.from_arrays would result in an error in conversion.
  • Improved performance of converting pykx.SymbolVector to numpy.array of strings, and also the conversion back from a numpy.array of strings to a q SymbolVector.
  • Improved performance of converting numpy.array's of dtypes datetime64/timedelta64 to the various pykx.TemporalTypes.

PyKX 1.0.1

Release Date

2022-03-18

Deprecations & Removals

  • The sync parameter for pykx.QConnection and pykx.QConnection.__call__ has been renamed to the less confusing name wait. The sync parameter remains, but its usage will result in a DeprecationWarning being emitted. The sync parameter will be removed in a future version.

Features & Fixes

  • Updated to stable classifier (Development Status :: 5 - Production/Stable) in project metadata. Despite this update being done in version 1.0.1, version 1.0.0 is still the first stable release of PyKX.
  • PyKX now provides source distributions (sdist). It can be downloaded from PyPI using pip download --no-binary=:all: --no-deps pykx. As noted in the installation docs, installations built from the source will only receive support on a best-effort basis.
  • Fixed Pandas NaT conversion to q types. Now pykx.toq(pandas.NaT, ktype=ktype) produces a null temporal atom for any given ktype (e.g. pykx.TimeAtom).
  • Added a doc page for limitations of embedded q.
  • Added a test to ensure large vectors are correctly handled (5 GiB).
  • Always use synchronous queries internally, i.e. fix QConnection(sync=False).
  • Disabled the context interface over IPC. This is a temporary measure that will be reversed once q function objects are updated to run in the environment they were defined in by default.
  • Reduced the time it takes to import PyKX. There are plans to reduce it further, as import pykx remains fairly slow.
  • Updated to KXI Core 2.1 & rename qce -> kxic.
  • Misc test updates.
  • Misc doc updates.

PyKX 1.0.0

Release Date

2022-02-14

Migration Notes

To switch from Pykdb to PyKX, you will need to update the name of the dependency from pykdb to pykx in your pyproject.toml/requirements.txt/setup.cfg/etc. When Pykdb was renamed to PyKX, its version number was reset. The first public release of PyKX has the version number 1.0.0, and will employ semantic versioning.

Pay close attention to the renames listed below, as well as the removals. Many things have been moved to the top-level, or otherwise reorganized. A common idiom with Pykdb was the following:

from pykdb import q, k

It is recommended that the following be used instead:

import pykx as kx

This way the many attributes at the top-level can be easily accessed without any loss of context, for example:

kx.q # Can be called to execute q code
kx.K # Base type for objects in q; can be used to convert a Python object into a q type
kx.SymbolAtom # Type for symbol atoms; can be used to convert a `str` or `bytes` into a symbol atom
kx.QContext # Represents a q context via the PyKX context interface
kx.QConnection # Can be called to connect to a q process via q IPC
kx.PyKXException # Base exception type for exceptions specific to PyKX and q
kx.QError # Exception type for errors that occur in q
kx.LicenseException # Exception type raised when features that require a license are used without
kx.QHOME # Path from which to load q files, set by $QHOME environment variable
kx.QARGS # List of arguments provided to the embedded q instance at startup, set by $QARGS environment variable
# etc.

You can no longer rely on the context being reset to the global context after each call into embedded q, however IPC calls are unaffected.

Renames

  • Pykdb has been renamed to PyKX. Pykdb -> PyKX; PYKDB -> PYKX; pykdb -> pykx.
  • The adapt module has been renamed to toq, and it can be called directly. Instead of pykdb.adapt.adapt(x) one should write pykx.toq(x).
  • The k module has been renamed to wrappers. All wrapper classes can be accessed from the top-level, i.e. pykx.K, pykx.SymbolAtom, etc.
  • The "module interface" (pykdb.module_interface) has been renamed to the "context interface" (pykx.ctx). All pykx.Q instances (i.e. pykx.q and all pykx.QConnection instances) have a ctx attribute, which is the global QContext for that pykx.Q instance. Usually, one need not directly access the global context. Instead, one can access its subcontexts directly e.g. q.dbmaint instead of q.ctx.dbmaint.
  • KdbError (and its subclasses) have been renamed to QError
  • pykdb.ctx.KdbContext has been renamed to pykx.ctx.QContext, and is available from the top-level, i.e. pykx.QContext.
  • The Connection class in the IPC module has been renamed to QConnection, and is now available at the top-level, i.e. pykx.QConnection.
  • The q type wrapper DynamicLoad has been renamed to Foreign (pykdb.k.DynamicLoad -> pykx.Foreign).

Deprecations & Removals

  • The pykdb.q.ipc attribute has been removed. The IPC module can be accessed directly instead at pykx.ipc, but generally one will only need to access the QConnection class, which can be accessed at the top-level: pykx.QConnection.
  • The pykdb.q.K attribute has been removed. Instead, K types can be used as constructors for that type by leveraging the toq module. For example, instead of pykdb.q.K(x) one should write pykx.K(x). Instead of pykx.q.K(x, k_type=pykx.k.SymbolAtom) one should write pykx.SymbolAtom(x) or pykx.toq(x, ktype=pykx.SymbolAtom).
  • Most KdbError/QError subclasses have been removed, as identifying them is error prone, and we are unable to provide helpful error messages for most of them.
  • The pykx.kdb singleton class has been removed.

Dependencies

  • More Numpy, Pandas, and PyArrow versions are supported. Current pandas~=1.0, numpy~=1.20,<1.22, and pyarrow>=3.0.0 are supported. PyArrow remains an optional dependency.
  • A dependency on find-libpython~=0.2 was added. This is only used when running PyKX under a q process (see details in the section below about new alpha features).
  • A dependency on the system library libcurl was added for Linux. This dependency will be made optional in a future release.

Features & Fixes

  • The pykx.Q class has been added as the base class for pykx.EmbeddedQ (the class for pykx.q) and pykx.QConnection.
  • The pykx.EmbeddedQ process now persists its context between calls.
  • The console now works over IPC.
  • The query module now works over IPC. Because K objects hold no reference to the q instance that created them (be it local or over IPC), K tables no longer have select/exec/update/delete methods with themselves projected in as the first argument. That is to say, instead of writing t.select(...), write q.qsql.select(t, ...), where q is either pykx.q or an instance of pykx.QConnection, and t was obtained from q.
  • The context interface now works over IPC.
  • Nulls and infinities are now handled as nulls and infinities, rather than as their underlying values. pykx.Atom.is_null, pykx.Atom.is_inf, pykx.Collection.has_nulls, and pykx.Collection.has_infs have been added. Numpy, Pandas, and PyArrow handles integral nulls with masked arrays, and they handle temporal nulls with NaT. NaN continues to be used for real/float nulls. The general Python representation (from .py()) uses K objects for nulls and infinities.
  • Calling bool on pykx.K objects now either raises a TypeError, or return the unambiguously correct result. For ambiguous cases such as pykx.Collection instances, use .any(), .all(), or a length check instead.
  • Assignment to q reserved words or the q context now raises a pykx.PyKXException.
  • pykx.toq.from_list (previously pykdb.adapt.adapt_list) now works in unlicensed mode.
  • q.query and q.sql are now placeholders (set to None). The query interface can be accessed from q.qsql.
  • Ternary pow now raises TypeError for RealNumericVector and RealNumericAtom.
  • QContext objects are now context handlers, e.g. with pykx.q.dbmaint: # operate in .dbmaint within this block. This context handler supports arbitrary nesting.
  • __getitem__ now raises a pykx.LicenseException when used in unlicensed mode. Previously it worked for a few select types only. If running in unlicensed mode, one should perform all q indexing in the connected q process, and all Python indexing after converting the K object to a Python/Numpy/Pandas/PyArrow object.
  • pykx.QConnection (previously pykdb.ipc.Connection) objects now have an informative/idiomatic repr.
  • Calls to pykx.q now support up to 8 arguments beyond the required query at position 0, similar to calling pykx.QConnection instances. These arguments are applied to the result of the query.
  • Embedded q is now used to count the number of rows a table has.
  • All dynamic linking to libq and libe has been replaced by dynamic loading. As a result, the modules previously known as adapt and adapt_unlicensed have been unified under pykx.toq.
  • PyKX now attempts to initialize embedded q when pykx is imported, rather than when pykx.q is first accessed. As a result, the error-prone practice of supplying the pykx.kdb singleton class with arguments for embedded q is now impossible.
  • Arguments for embedded q can now be supplied via the environment variable $QARGS in the form of command-line arguments. For example, QARGS='--unlicensed' causes PyKX to enter unlicensed mode when it is started, and QARGS='-o 8' causes embedded q to use an offset from UTC of 8 hours. These could be combined as QARGS='--unlicensed -o 8'.
  • Added the --licensed startup flag (to be provided via the $QARGS environment variable), which can be used to raise a pykx.PyKXException (rather than emitting a warning) if PyKX fails to start in licensed mode (likely because of a missing/invalid q license).
  • PyKX Linux wheels are now PEP 600 compliant, built to the manylinux_2_17 standard.
  • Misc other bug fixes.
  • Misc doc improvements.

Performance Improvements

  • Converting nested lists from q to Python is much faster.
  • Internally, PyKX now calls q functions with arguments directly instead of creating a pykx.Function instance then calling it. This results in modest performance benefits in some cases.
  • The context interface no longer loads every element of a context when the context is first accessed, thereby removing the computation spike, which could be particularly intense for large q contexts.

New Alpha Features

Alpha features are subject to change

Alpha features are not stable will be subject to changes without notice. Use at your own risk.

  • q can now load PyKX by loading the q file pykx.q. pykx.q can be copied into $QHOME by running pykx.install_into_QHOME(). When loaded into q, it will define the .pykx namespace, which notably has .pykx.exec and .pykx.pyeval. This allows for Python code to be run within q libraries and applications without some of the limitations of embedded q such as the lack of the q main loop, or the lack of timers. When q loads pykx.q, it attempts to source the currently active Python environment by running python, then fetching the environment details from it.