* Add math.isqrt function computing the integer square root.
* Code cleanup: remove redundant comments, rename some variables.
* Tighten up code a bit more; use Py_XDECREF to simplify error handling.
* Update Modules/mathmodule.c
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Update Modules/mathmodule.c
Use real argument clinic type instead of an alias
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Add proof sketch
* Updates from review.
* Correct and expand documentation.
* Fix bad reference handling on error; make some variables block-local; other tidying.
* Style and consistency fixes.
* Add missing error check; don't try to DECREF a NULL a
* Simplify some error returns.
* Another two test cases:
- clarify that floats are rejected even if they happen to be
squares of small integers
- TypeError beats ValueError for a negative float
* Add fast path for small inputs. Needs tests.
* Speed up isqrt for n >= 2**64 as well; add extra tests.
* Reduce number of test-cases to avoid dominating the run-time of test_math.
* Don't perform unnecessary extra iterations when computing c_bit_length.
* Abstract common uint64_t code out into a separate function.
* Cleanup.
* Add a missing Py_DECREF in an error branch. More cleanup.
* Update Modules/mathmodule.c
Add missing `static` declaration to helper function.
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Add missing backtick.
* Add math.isqrt function computing the integer square root.
* Code cleanup: remove redundant comments, rename some variables.
* Tighten up code a bit more; use Py_XDECREF to simplify error handling.
* Update Modules/mathmodule.c
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Update Modules/mathmodule.c
Use real argument clinic type instead of an alias
Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>
* Add proof sketch
* Updates from review.
* Correct and expand documentation.
* Fix bad reference handling on error; make some variables block-local; other tidying.
* Style and consistency fixes.
* Add missing error check; don't try to DECREF a NULL a
* Simplify some error returns.
* Another two test cases:
- clarify that floats are rejected even if they happen to be
squares of small integers
- TypeError beats ValueError for a negative float
* Documentation and markup improvements; thanks Serhiy for the suggestions!
* Cleaner Misc/NEWS entry wording.
* Clean up (with one fix) to the algorithm explanation and proof.
The overflow check was relying on undefined behaviour as it was using the result of the multiplication to do the check, and once the overflow has already happened, any operation on the result is undefined behaviour.
Some extra checks that exercise code paths related to this are also added.
The standard math library (libm) may follow IEEE-754 recommendation to
include an implementation of sinPi(), i.e. sinPi(x):=sin(pi*x).
And this triggers a name clash, found by FreeBSD developer
Steve Kargl, who worken on putting sinpi into libm used on FreeBSD
(it has to be named "sinpi", not "sinPi", cf. e.g.
https://en.cppreference.com/w/c/experimental/fpext4).
Use the fast call convention for math functions atan2(),
copysign(), hypot() and remainder() and inline unpacking
arguments. This sped up them by 1.3--2.5 times.
