"Generally, mixed-mode arithmetic combining real and complex variables should
be performed directly, not by first coercing the real to complex, lest the sign
of zero be rendered uninformative; the same goes for combinations of pure
imaginary quantities with complex variables." (c) Kahan, W: Branch cuts for
complex elementary functions.
This patch implements mixed-mode arithmetic rules, combining real and
complex variables as specified by C standards since C99 (in particular,
there is no special version for the true division with real lhs
operand). Most C compilers implementing C99+ Annex G have only these
special rules (without support for imaginary type, which is going to be
deprecated in C2y).
Co-authored-by: Sergey B Kirpichev <skirpichev@gmail.com>
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
* Remove the equivalence with real+imag*1j which can be incorrect in corner
cases (non-finite numbers, the sign of zeroes).
* Separately document the three roles of the constructor: parsing a string,
converting a number, and constructing a complex from components.
* Document positional-only parameters of complex(), float(), int() and bool()
as positional-only.
* Add examples for complex() and int().
* Specify the grammar of the string for complex().
* Improve the grammar of the string for float().
* Describe more explicitly the behavior when real and/or imag arguments are
complex numbers. (This will be deprecated in future.)
* Use new-style index directive ('module') - C API
* Use new-style index directive ('module') - Library
* Use new-style index directive ('module') - Reference
* Use new-style index directive ('module') - Tutorial
* Uncomment module removal in pairindextypes
* Use new-style index directive ('module') - C API
* Use new-style index directive ('module') - Library
* Use new-style index directive ('module') - Reference
This PR updates the cmath module documentation to reflect the reality that Python is almost always (and as far as I can tell, that "almost" can be omitted) running on a machine whose C double supports signed zeros.
* Removes misleading references to functions being continuous from above / below / the left / the right at branch cuts
* Expands the note on branch cuts at the top of the module documentation to explain the double-sided sign-of-zero-based behaviour
For details, see:
PEP 0485 -- A Function for testing approximate equality
Functions added: math.isclose() and cmath.isclose().
Original code by Chris Barker. Patch by Tal Einat.
svn+ssh://pythondev@svn.python.org/python/trunk
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r77230 | mark.dickinson | 2010-01-02 14:29:52 +0000 (Sat, 02 Jan 2010) | 1 line
Clarify that the rect, phase and polar functions work with radians.
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svn+ssh://pythondev@svn.python.org/python/trunk
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r74184 | georg.brandl | 2009-07-23 08:08:58 +0100 (Thu, 23 Jul 2009) | 1 line
#6548: dont suggest existence of real and imag functions in cmath.
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r74230 | mark.dickinson | 2009-07-28 17:12:40 +0100 (Tue, 28 Jul 2009) | 4 lines
Issue #6458: Reorganize cmath documentation into sections (similar to
the way that the math documentation is organized); clarify section on
conversions to and from polar coordinates.
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svn+ssh://pythondev@svn.python.org/python/trunk
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r64434 | andrew.kuchling | 2008-06-20 18:13:58 -0500 (Fri, 20 Jun 2008) | 1 line
Remove request for e-mail; it's unlikely these classes will be saved
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r64435 | andrew.kuchling | 2008-06-20 18:14:32 -0500 (Fri, 20 Jun 2008) | 1 line
Grammar fixes
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r64440 | andrew.kuchling | 2008-06-21 08:29:12 -0500 (Sat, 21 Jun 2008) | 1 line
Docstring typo
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r64441 | andrew.kuchling | 2008-06-21 08:47:20 -0500 (Sat, 21 Jun 2008) | 1 line
Use repr() for bad input strings; this makes the empty string or binary characters more visible
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r64442 | andrew.kuchling | 2008-06-21 08:48:38 -0500 (Sat, 21 Jun 2008) | 1 line
Docstring correction
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r64443 | georg.brandl | 2008-06-21 09:26:19 -0500 (Sat, 21 Jun 2008) | 2 lines
Documentation fix.
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r64445 | facundo.batista | 2008-06-21 12:30:06 -0500 (Sat, 21 Jun 2008) | 3 lines
Reviewed and updated the documentation. Fixes#3017.
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r64447 | facundo.batista | 2008-06-21 13:58:04 -0500 (Sat, 21 Jun 2008) | 6 lines
Now a from submitted via POST that also has a query string
will contain both FieldStorage and MiniFieldStorage items.
Fixes#1817.
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r64448 | facundo.batista | 2008-06-21 14:48:19 -0500 (Sat, 21 Jun 2008) | 5 lines
In the deprecated functions I added an alert to review
specially a section of the subprocess documentation
that helps with the replacing of those functionss.
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r64450 | georg.brandl | 2008-06-22 04:05:29 -0500 (Sun, 22 Jun 2008) | 2 lines
Turn section references into proper cross-references.
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r64452 | facundo.batista | 2008-06-22 08:36:20 -0500 (Sun, 22 Jun 2008) | 5 lines
Issue #2722. Now the char buffer to support the path string has
not fixed length, it mallocs memory if needed. As a result, we
don't have a maximum for the getcwd() method.
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r64455 | facundo.batista | 2008-06-22 10:27:10 -0500 (Sun, 22 Jun 2008) | 4 lines
Issue 3164. Small fix to don't repeat a comparation
without necessity.
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r64461 | georg.brandl | 2008-06-22 13:11:52 -0500 (Sun, 22 Jun 2008) | 2 lines
#3085: Fix syntax error.
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r64464 | georg.brandl | 2008-06-22 13:31:54 -0500 (Sun, 22 Jun 2008) | 2 lines
Expand docstrings of sqlite3 functions.
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r64466 | georg.brandl | 2008-06-22 14:07:59 -0500 (Sun, 22 Jun 2008) | 2 lines
Write out "phi" consistently.
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r64468 | facundo.batista | 2008-06-22 14:35:24 -0500 (Sun, 22 Jun 2008) | 4 lines
Just returning nothing instead of rising TestSkipped, because
it makes the test fail in the trunk.loewis-sun buildbot.
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svn+ssh://pythondev@svn.python.org/python/trunk
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r62380 | christian.heimes | 2008-04-19 01:13:07 +0200 (Sat, 19 Apr 2008) | 3 lines
I finally got the time to update and merge Mark's and my trunk-math branch. The patch is collaborated work of Mark Dickinson and me. It was mostly done a few months ago. The patch fixes a lot of loose ends and edge cases related to operations with NaN, INF, very small values and complex math.
The patch also adds acosh, asinh, atanh, log1p and copysign to all platforms. Finally it fixes differences between platforms like different results or exceptions for edge cases. Have fun :)
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r62382 | christian.heimes | 2008-04-19 01:40:40 +0200 (Sat, 19 Apr 2008) | 2 lines
Added new files to Windows project files
More Windows related fixes are coming soon
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r62383 | christian.heimes | 2008-04-19 01:49:11 +0200 (Sat, 19 Apr 2008) | 1 line
Stupid me. Py_RETURN_NAN should actually return something ...
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Sergey B Kirpichev
Zhikang Yan
Serhiy Storchaka
Ned Batchelder
F3eQnxN3RriK
Adam Turner
Mark Dickinson
Georg Brandl
Guido van Rossum
Terry Jan Reedy
Tal Einat
Benjamin Peterson
Christian Heimes