Commit Graph

100 Commits

Author SHA1 Message Date
Raymond Hettinger
4e0ce82058 Revert "bpo-26680: Incorporate is_integer in all built-in and standard library numeric types (GH-6121)" (GH-22584)
This reverts commit 58a7da9e12.
2020-10-07 16:43:44 -07:00
Robert Smallshire
58a7da9e12 bpo-26680: Incorporate is_integer in all built-in and standard library numeric types (GH-6121)
* bpo-26680: Adds support for int.is_integer() for compatibility with float.is_integer().

The int.is_integer() method always returns True.

* bpo-26680: Adds a test to ensure that False.is_integer() and True.is_integer() are always True.

* bpo-26680: Adds Real.is_integer() with a trivial implementation using conversion to int.

This default implementation is intended to reduce the workload for subclass
implementers. It is not robust in the presence of infinities or NaNs and
may have suboptimal performance for other types.

* bpo-26680: Adds Rational.is_integer which returns True if the denominator is one.

This implementation assumes the Rational is represented in it's
lowest form, as required by the class docstring.

* bpo-26680: Adds Integral.is_integer which always returns True.

* bpo-26680: Adds tests for Fraction.is_integer called as an instance method.

The tests for the Rational abstract base class use an unbound
method to sidestep the inability to directly instantiate Rational.
These tests check that everything works correct as an instance method.

* bpo-26680: Updates documentation for Real.is_integer and built-ins int and float.

The call x.is_integer() is now listed in the table of operations
which apply to all numeric types except complex, with a reference
to the full documentation for Real.is_integer().  Mention of
is_integer() has been removed from the section 'Additional Methods
on Float'.

The documentation for Real.is_integer() describes its purpose, and
mentions that it should be overridden for performance reasons, or
to handle special values like NaN.

* bpo-26680: Adds Decimal.is_integer to the Python and C implementations.

The C implementation of Decimal already implements and uses
mpd_isinteger internally, we just expose the existing function to
Python.

The Python implementation uses internal conversion to integer
using to_integral_value().

In both cases, the corresponding context methods are also
implemented.

Tests and documentation are included.

* bpo-26680: Updates the ACKS file.

* bpo-26680: NEWS entries for int, the numeric ABCs and Decimal.

Co-authored-by: Robert Smallshire <rob@sixty-north.com>
2020-10-01 17:30:08 +01:00
Niklas Fiekas
8bd216dfed bpo-29882: Add an efficient popcount method for integers (#771)
* bpo-29882: Add an efficient popcount method for integers

* Update 'sign bit' and versionadded in docs

* Add entry to whatsnew document

* Doc: use positive example, mention population count

* Minor cleanups of the core code

* Move popcount_digit closer to where it's used

* Use z instead of self after conversion

* Add 'absolute value' and 'population count' to docstring

* Fix clinic error about missing summary line

* Ensure popcount_digit is portable with 64-bit ints

Co-authored-by: Mark Dickinson <dickinsm@gmail.com>
2020-05-29 17:28:02 +01:00
HongWeipeng
036fe85bd3 bpo-27145: small_ints[x] could be returned in long_add and long_sub (GH-15716) 2019-11-26 16:54:49 +09:00
Serhiy Storchaka
b2e2025941 bpo-33073: Rework int.as_integer_ratio() implementation (GH-9303)
* Simplify the C code.
* Simplify tests and make them more strict and robust.
* Add references in the documentation.
2018-10-19 23:46:31 +02:00
Benjamin Peterson
cbda8fc5d7 closes bpo-34868: Improve error message with '_' is combined with an invalid type specifier. (GH-9666) 2018-10-01 21:54:39 -07:00
Lisa Roach
5ac704306f bpo-33073: Adding as_integer_ratio to ints. (GH-8750) 2018-09-13 23:56:23 -07:00
INADA Naoki
16dfca4d82 bpo-34087: Fix buffer overflow in int(s) and similar functions (GH-8274)
`_PyUnicode_TransformDecimalAndSpaceToASCII()` missed trailing NUL char.
It caused buffer overflow in `_Py_string_to_number_with_underscores()`.

This bug is introduced in 9b6c60cb.
2018-07-14 12:06:43 +09:00
Serhiy Storchaka
918403cfc3 bpo-29816: Shift operation now has less opportunity to raise OverflowError. (#680)
ValueError always is raised rather than OverflowError for negative counts.
Shifting zero with non-negative count always returns zero.
2017-03-30 09:47:07 +03:00
Eric V. Smith
89e1b1aae0 Issue 27080: PEP 515: add '_' formatting option. 2016-09-09 23:06:47 -04:00
Raymond Hettinger
3b09cd64e0 Merge 2016-09-03 01:55:39 -07:00
Raymond Hettinger
f0f1c239e4 Issue 27936: Fix inconsistent round() behavior between float and int 2016-09-03 01:55:11 -07:00
Mark Dickinson
82a95277b8 Issue #27870: A left shift of zero by a large integer no longer attempts to allocate large amounts of memory. 2016-08-29 19:27:06 +01:00
Serhiy Storchaka
ea36c941a1 Issue #23640: int.from_bytes() no longer bypasses constructors for subclasses. 2016-05-12 10:37:58 +03:00
Serhiy Storchaka
1f364438ad Issue #23640: int.from_bytes() no longer bypasses constructors for subclasses. 2016-05-12 10:39:32 +03:00
Yury Selivanov
e0b23095ee Issues #26289 and #26315: Optimize floor/modulo div for single-digit longs
Microbenchmarks show 2-2.5x improvement.  Built-in 'divmod' function
is now also ~10% faster.

-m timeit -s "x=22331" "x//2;x//-3;x//4;x//5;x//-6;x//7;x//8;x//-99;x//100;"
with patch: 0.321          without patch: 0.633

-m timeit -s "x=22331" "x%2;x%3;x%-4;x%5;x%6;x%-7;x%8;x%99;x%-100;"
with patch: 0.224          without patch: 0.66

Big thanks to Serhiy Storchaka, Mark Dickinson and Victor Stinner for
thorow code reviews and algorithms improvements.
2016-02-11 10:26:27 -05:00
Martin Panter
429f28d1ae Issue #25211: Merge test_long from 3.4 into 3.5 2015-09-26 00:07:29 +00:00
Martin Panter
cbe16aefb8 Issue #25211: Eliminate lazy error message class by using subTest
Some of the calls to the Frm class were buggy anyway.
2015-09-25 23:50:47 +00:00
Zachary Ware
38c707e7e0 Issue #21741: Update 147 test modules to use test discovery.
I have compared output between pre- and post-patch runs of these tests
to make sure there's nothing missing and nothing broken, on both
Windows and Linux.  The only differences I found were actually tests
that were previously *not* run.
2015-04-13 15:00:43 -05:00
Serhiy Storchaka
08448a1f4d Issue #23326: Removed __ne__ implementations. Since fixing default __ne__
implementation in issue #21408 they are redundant.
2015-01-31 12:05:05 +02:00
Victor Stinner
7fe1049fcb Issue #21422: Add a test to check that bool << int and bool >> int return an int 2014-05-12 22:35:40 +02:00
Serhiy Storchaka
6c9678e1a5 Issue #20546: Use specific asserts in int tests. 2014-02-08 14:29:36 +02:00
Serhiy Storchaka
3a20a5dead Issue #20546: Use specific asserts in int tests. 2014-02-08 14:28:33 +02:00
Serhiy Storchaka
46e1ce214b Issue #18783: Removed existing mentions of Python long type in docstrings,
error messages and comments.
2013-08-27 20:17:03 +03:00
Serhiy Storchaka
9594942716 Issue #18783: Removed existing mentions of Python long type in docstrings,
error messages and comments.
2013-08-27 19:40:23 +03:00