=========
BytesFunc
=========
:Authors:
Michael Griffin
:Version: 3.4.1 for 2023-04-22
:Copyright: 2014 - 2023
:License: This document may be distributed under the Apache 2.0 License.
:Language: Python 3.6 or later
---------------------------------------------------------------------
Introduction
============
The BytesFunc module provides high speed array processing functions for use with
Python 'bytes' and 'bytearray' objects. These functions are patterned after the
functions in the standard Python "operator" module together with some additional
ones from other sources.
The purpose of these functions is to perform mathematical calculations on
"bytes" and "bytearray" objects significantly faster than using native Python.
See full documentation at: https://bytesfunc.readthedocs.io/en/latest/
If you are installing on an ARM platform such as the Raspberry Pi, see the
installation notes at the end before attempting to install from PyPI using PIP.
---------------------------------------------------------------------
Function Summary
================
The compare operators used for 'ball', 'bany', and 'findindex' are examples
only, and other compare operations are available. Many functions will accept
other parameter combinations of sequences and numeric parameters. See the
details for each function for what parameter combinations are valid.
Brief Description
-----------------
=========== ==================================================
Function Equivalent to
=========== ==================================================
and\_ Perform a bitwise AND across the sequence.
ball True if all elements of the sequence meet the match criteria.
bany True if any elements of the sequence meet the match criteria.
bmax Return the maximum value in the sequence.
bmin Return the minimum value in the sequence.
bsum Return the sum of the sequence.
eq True if all elements of the sequence equal the compare value.
findindex Returns the index of the first value in an array to meet the
specified criteria.
ge True if all elements of the sequence are greater than or equal to
the compare value.
gt True if all elements of the sequence are greater than the compare
value.
invert Perform a bitwise invert across the sequence.
le True if all elements of the sequence are less than or equal to the
compare value.
lshift Perform a bitwise left shift across the sequence.
lt True if all elements of the sequence are less than the compare
value.
ne True if all elements of the sequence are not equal the compare
value.
or\_ Perform a bitwise OR across the sequence.
rshift Perform a bitwise right shift across the sequence.
xor Perform a bitwise XOR across the sequence.
=========== ==================================================
Python Equivalent
-----------------
=========== ==================================================
Function Equivalent to
=========== ==================================================
and\_ [x & param for x in sequence1]
ball all([(x > param) for x in array])
bany any([(x > param) for x in array])
bmax max(sequence)
bmin min(sequence)
bsum sum(sequence)
eq all([x == param for x in sequence])
findindex [x for x,y in enumerate(array) if y > param][0]
ge all([x >= param for x in sequence])
gt all([x > param for x in sequence])
invert [~x for x in sequence1]
le all([x <= param for x in sequence])
lshift [x << param for x in sequence1]
lt all([x < param for x in sequence])
ne all([x != param for x in sequence])
or\_ [x | param for x in sequence1]
rshift [x >> param for x in sequence1]
xor [x ^ param for x in sequence1]
=========== ==================================================
---------------------------------------------------------------------
Supported Sequence Types
========================
BytesFunc supports Python native "bytes" and "bytearray" objects.
---------------------------------------------------------------------
Performance
===========
Average performance increase on x86_64 Ubuntu with GCC is 600 times faster
than native Python. Performance will vary depending on the function,
with the performance increase ranging from 7 times to 1500 times.
Other platforms show similar improvements.
Detailed performance figures are listed in the full documentation.
---------------------------------------------------------------------
Platform support
================
BytesFunc is written in 'C' and uses the standard C libraries to implement the
underlying math functions. BytesFunc has been tested on the following platforms.
======================= ========== ====== =============== ================
OS Hardware Bits Compiler Python Version
======================= ========== ====== =============== ================
Debian 11 i686 32 GCC 3.9.2
Debian 11 x86_64 64 GCC 3.9.2
Ubuntu 22.04 x86_64 64 GCC 3.10.6
Ubuntu 23.04 x86_64 64 GCC 3.11.2
opensuse-leap 15.4 x86_64 64 GCC 3.6.15
almalinux 9.1 x86_64 64 GCC 3.9.14
alpine 3.17.3 i686 32 GCC 3.10.11
FreeBSD 13.2 amd64 64 Clang 3.9.16
OpenBSD 7.3 amd64 64 Clang 3.10.10
MS Windows 10 AMD64 64 MSC 3.11.0
MS Windows 11 AMD64 64 MSC 3.11.0
Raspbian 11 armv7l 32 GCC 3.9.2
Ubuntu 22.04 aarch64 64 GCC 3.10.6
======================= ========== ====== =============== ================
amd64 is another name for x86_64 and does not indicate the CPU brand.
armv7l is 32 bit ARM. The test hardware is a Raspberry Pi 3.
aarch64 is 64 bit ARM. The test hardware is a Raspberry Pi 4.
* The Rasberry Pi 3 tests were conducted on a Raspberry Pi 3 ARM CPU running
in 32 bit mode.
* The Ubuntu ARM tests were conducted on a Raspberry Pi 4 ARM CPU running in
64 bit mode.
* All others were conducted using VMs running on x86 hardware.
---------------------------------------------------------------------
Installation
============
Please note that this is a Python 3 package. To install using Pip, you will
need (with Debian package in brackets):
* The appropriate C compiler and header files (gcc and build-essential).
* The Python3 development headers (python3-dev).
* Pip3 together with the corresponding Setuptools (python3-pip).
example::
# Install from PyPI.
pip3 install bytesfunc
# Force install from PyPI source instead of using a binary wheel.
pip3 install --user --force-reinstall --no-binary=:all: bytesfunc
# Install from a local copy of the source package (Linux).
pip3 install --no-index --find-links=. bytesfunc
# Install a local package as a user package.
pip3 install --user --no-index --find-links=. bytesfunc
# Windows, FreeBSD, and OpenBSD seems to use "pip" instead
# of "pip3" for some reason.
pip install bytesfunc
Newer versions of OpenBSD and FreeBSD will not install this package correctly
when running setup.py directly. Use pip to install, even for local package
installs. Testing of this package has been changed to use only pip (or pip3)
in order to provide a common testing method for all platforms. Testing using
setup.py directly is no longer done.
Recent versions of PyPI seem to be building their own binary wheels for some
platforms using their own infrastruction. This may result in an invalid ARM
binary on Raspberry Pi.
If you have difficulties, then either download the tar.gz version and install
it locally (see the above instructions for a local install). Alternatively,
see the above example for how to force a binary install instead of using a
wheel. There is also a bash script called "setupuser.sh" which will call setup.
py directly with the appropriate parameters.
The setup.py file has platform detection code which it uses to pass the
correct flags to the C compiler. For ARM, this includes the CPU type. If you
are using an ARM CPU type which is not recognized then setup.py may not
compile in SIMD features. You can experiment with modifying setup.py to add
new ARM models, but be sure that anything you try is compatible with the
existing ones.
Installing on Linux with PIP and PEP-668
----------------------------------------
PEP-668 (PEPs describe changes to Python) introduced a new feature which can
affect how packages are installed with PIP. If PIP is configured to be
EXTERNALLY-MANAGED it will refuse to install a package outside of a virtual
environment.
The intention of this is to prevent conflicts between packages which are
installed using the system package manager, and ones which are installed using
PIP.
Linux distros which are affeced by this include the latest versions of Debian
and Ubuntu.
As this package is a library which is intended to be used by other
applications, there is no one right way to install it, whether inside or
outside of a virtual environment. Review the options available with PIP to see
what is suitable for your application.
For testing purposes this package was installed by setting the environment
variable PIP_BREAK_SYSTEM_PACKAGES to "1", which effectively disables this
feature in PIP.
example::
export PIP_BREAK_SYSTEM_PACKAGES=1
---------------------------------------------------------------------
Release History
===============
* 3.4.1 - Update to testing and support. There were no code. changes.
Ubuntu version updated to 23.04. AlmaLinux updated to 9.1.
Alpine Linux updated to 3.17.3. FreeBSD updated to 13.2.
OpenBSD updated to 7.3.
On Ubuntu 23.04, the installation method has changed due to how
PEP-668 was implemented by Debian and how this affects "pip".
Some other distros may experience the same problems if they made
the same changes. See the README.TxT for details.
* 3.4.0 - Added pyproject.toml file to satisfy Python 3.11 requirements.
Updated build scripts to use python3 -m build instead of calling
setup.py directly. Test targets were updated, Ubuntu 20.04 was
dropped, Ubuntu 22.10 was added, FreeBSD python version upgraded
to 3.9, OpenBSD upgraded to 7.2, Windows 10 Python upgraded to 3.11,
Windows 11 Python upgraded to 3.11. Added __version__ attribute to
allow checking package version number at run time. Added version
unit test. Updated setup.py and other files to allow the version
number to be automatically updated from a single source at build
time.
* 3.3.0 - Major performance improvements for bsum through the use of SIMD and
other optimizations. Used splint (GCC lint) on all C code and fixed
warnings. Other than bsum, no changes in functionality.
* 3.2.1 - Fixed formatting error in README.rst.
* 3.2.0 - Update to testing and support. Tested with new releases of Ubuntu
22.04 and OpenBSD 7.1. Changed "simdsupport" to also report the
architecture the binary was compiled for. "Simdsupport" is only
used for testing and benchmarking and is not a stable part of
the release.
* 3.1.2 - Bump to correct minor documentation error in README.rst.
* 3.1.1 - Update to testing and support. Raspberry Pi 32 bit OS updated to
version 2022-04-04. Update to setup.py to improve ARM version
detection.
* 3.1.0 - Update to testing and support. On Windows 10 the Python version is
3.10. Centos has been replaced by AlmaLinux due to Red Hat ending
long term support for Centos. Ubuntu Server 21.04 replaced by 21.10.
No actual code changes.
* 3.0.0 - Major speed improvement to lshfit and rshift on x86-64 due to adding
SIMD support. Debian test platforms were updated to latest versions
(11).
* 2.2.0 - Updated benchmarks to make each one a separate file. Centos and
OpenSuse test platforms updated to latest versions.
* 2.1.1 - Documentation updated and version number bumped to reflect testing
with Ubuntu 21.04, FreeBSD 13.0, and OpenBSD 6.9. No code changes.
* 2.1.0 - Changed setup.py to detect Raspberry Pi 4 and set the compiler args
accordingly. Added support for Pi 4. Dropped testing of 64 bit
mode on Pi 3.
* 2.0.1 - Documentation updated to reflect testing with the release version
of Ubuntu 20.04 ARM (Rasberry Pi), Ubuntu 2010 (x86-64), OpenBSD 6.8,
and Python 3.9 on Windows. No code changes and no change in version
number.
* 2.0.0 - Documentation updated to reflect testing with the release version
of Ubuntu 20.04. No code changes and no change in version number.
* 2.0.0 - Added SIMD support for ARMv8 AARCH64. This is 64 bit ARM on a
Raspberry Pi3 when running 64 bit Ubuntu. Raspbian is 32 bit only
and has 64 bit SIMD vectors. 64 bit ARM has 128 bit SIMD vectors
and so offers improved performance.
* 1.0.0 - First release.