Python bindings for CRlibm, an efficient and proven correctly-rounded mathematical library.
CRlibm is a free mathematical library (libm) which provides:
- implementations of the double-precision C99 standard elementary functions,
- correctly rounded in the four IEEE-754 rounding modes,
- with a comprehensive proof of both the algorithms used and their implementation,
- sufficiently efficient in average time, worst-case time, and memory consumption to replace existing libms transparently.
At the command line:
$ pip install crlibm
On Microsoft Windows pip will try first to download a binary
archive in wheel format, and if no such a wheel can be found for
your Python version, pip will try to compile the library. In
order to do so, it is strongly recommended to have MinGW-w64 installed under MSYS2, for instance by following the
instructions in http://stackoverflow.com/a/30071634.
In Python:
>>> import crlibm >>> crlibm.exp_ru(1) 2.7182818284590455 >>> crlibm.exp_rd(1) 2.718281828459045
- This project provides the bindings for the functions in the following table:
| f(x) | Round to nearest | Round up (to +∞) | Round down (to -∞) | Round to 0 |
| Exponentials and logarithms | ||||
| exp(x) | exp_rn | exp_ru | exp_rd | exp_rz |
| exp(x)-1 | expm1_rn | expm1_ru | expm1_rd | expm1_rz |
| log(x) | log_rn | log_ru | log_rd | log_rz |
| log(1+x) | log1p_rn | log1p_ru | log1p_rd | log1p_rz |
| log(x)/log(2) | log2_rn | log2_ru | log2_rd | log2_rz |
| log(x)/log(10) | log10_rn | log10_ru | log10_rd | log10_rz |
| sinh(x) | sinh_rn | sinh_ru | sinh_rd | sinh_rz |
| cosh(x) | cosh_rn | cosh_ru | cosh_rd | cosh_rz |
| Trigonometry | ||||
| sin(x) | sin_rn | sin_ru | sin_rd | sin_rz |
| cos(x) | cos_rn | cos_ru | cos_rd | cos_rz |
| tan(x) | tan_rn | tan_ru | tan_rd | tan_rz |
| asin(x) | asin_rn | asin_ru | asin_rd | asin_rz |
| acos(x) | acos_rn | acos_ru | acos_rd | acos_rz |
| atan(x) | atan_rn | atan_ru | atan_rd | atan_rz |
| Trigonometry in multiples of π | ||||
| sin(π * x) | sinpi_rn | sinpi_ru | sinpi_rd | sinpi_rz |
| cos(π * x) | cospi_rn | cospi_ru | cospi_rd | cospi_rz |
| tan(π * x) | tanpi_rn | tanpi_ru | tanpi_rd | tanpi_rz |
| asin(x)/π | asinpi_rn | asinpi_ru | asinpi_rd | asinpi_rz |
| acos(x)/π | acospi_rn | acospi_ru | acospi_rd | acospi_rz |
| atan(x)/π | atanpi_rn | atanpi_ru | atanpi_rd | atanpi_rz |
- The function
powin CRlibm is not exported.
Both the CRlibm library and the Python bindings are distributed under the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
David Defour, Catherine Daramy, Florent de Dinechin, Matthieu Gallet, Nicolas Gast, Christoph Lauter, Jean-Michel Muller.
Python bindings by Stefano Taschini.
- Project home page: https://github.com/taschini/pycrlibm.
- Documentation: https://pycrlibm.readthedocs.io.
- Entry in the Python Package Index: https://pypi.python.org/pypi/crlibm.
- CRlibm home page: http://lipforge.ens-lyon.fr/www/crlibm.
- LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.