1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182
|
Tinyarray
=========
Tinyarrays are similar to NumPy arrays, but optimized for small sizes.
Common operations on very small arrays are to 3-7 times faster than with
NumPy (with NumPy 1.6 it used to be up to 35 times), and 3 times less
memory is used to store them. Tinyarrays are useful if you need many
small arrays of numbers, and cannot combine them into a few large ones.
(The resulting code is still much slower than C, but it may now be fast
enough.)
Unlike Python's built-in tuples, Tinyarrays support mathematical
operations like element-wise addition and matrix multiplication. Unlike
Numpy arrays, Tinyarrays can be used as dictionary keys because they are
hashable and immutable. What is more, tinyarrays are equivalent to
tuples with regard to hashing and comparisons: a dictionary or set with
tinyarray keys may by transparently indexed by tuples.
The module's interface is a subset of that of NumPy and thus should be
familiar to many. Whenever an operation is missing from Tinyarray,
NumPy functions can be used directly with Tinyarrays.
Tinyarray is licensed under the "simplified BSD License". See
`<LICENSE.rst>`_.
Website: https://gitlab.kwant-project.org/kwant/tinyarray
Please report bugs here:
https://gitlab.kwant-project.org/kwant/tinyarray/issues
Source code
-----------
Source tarballs are available at http://downloads.kwant-project.org/tinyarray/
Clone the Git repository with ::
git clone https://gitlab.kwant-project.org/kwant/tinyarray.git
Installation
------------
Tinyarray can be built from source with the usual ::
pip install tinyarray
One can also download the source tarball (or clone it from git) and use ::
python setup.py install
Prepared packages exist for
* Windows
Use `Christoph Gohlke's installer
<http://www.lfd.uci.edu/~gohlke/pythonlibs/#tinyarray>`_.
* Ubuntu and derivatives ::
sudo apt-add-repository ppa:kwant-project/ppa
sudo apt-get update
sudo apt-get install python-tinyarray
* Debian and derivatives
1. Add the following lines to ``/etc/apt/sources.list``::
deb http://downloads.kwant-project.org/debian/ stable main
deb-src http://downloads.kwant-project.org/debian/ stable main
2. (Optional) Add the OpenPGP key used to sign the repositories by executing::
sudo apt-key adv --keyserver pgp.mit.edu --recv-key C3F147F5980F3535
3. Update the package data, and install::
sudo apt-get update
sudo apt-get install python-tinyarray
* Mac OS X
Follow the `instructions for installing "Kwant"
<http://kwant-project.org/install#mac-os-x>`_ but install
``py27-tinyarray`` instead of ``py27-kwant`` etc.
Build configuration
-------------------
If necessary, the compilation and linking of tinyarray can be configured with
a build configuration file. By default, this file is ``build.conf`` in the
root directory of the tinyarray distribution. A different path may be
provided using the ``--configfile=PATH`` option.
The configuration file consists of sections, one for each extension module
(currently there is only one: ``tinyarray``), led by a ``[section name]``
header and followed by ``key = value`` lines.
Possible keys are the keyword arguments for ``distutils.core.Extension`` (For
a complete list, see its `documentation
<https://docs.python.org/3/distutils/apiref.html#distutils.core.Extension>`_).
The corresponding values are whitespace-separated lists of strings.
Example ``build.conf`` for compiling Tinyarray with C assertions::
[tinyarray]
undef_macros = NDEBUG
Usage example
-------------
The following example shows that in simple cases Tinyarray works just as
NumPy. ::
from math import sin, cos, sqrt
import tinyarray as ta
# Make a vector.
v = ta.array([1.0, 2.0, 3.0])
# Make a rotation matrix.
alpha = 0.77
c, s = cos(alpha), sin(alpha)
rot_z = ta.array([[c, -s, 0],
[s, c, 0],
[0, 0, 1]])
# Rotate the vector, normalize, and print it.
v = ta.dot(rot_z, v)
v /= sqrt(ta.dot(v, v))
print v
Documentation
-------------
The module's interface is a basic subset of NumPy and hence should be familiar
to many Python programmers. All functions are simplified versions of their
NumPy counterparts. The module's docstring serves as main documentation. To
see it, run in Python::
import tinyarray as ta
help(ta)
Or in the system shell::
pydoc tinyarray
Contributing
------------
Contributions to tinyarray are most welcome. Patches may be sent by email, or
a merge request may be opened on the Project's website.
Please add tests for any new functionality and make sure that all existing
tests still run. To run the tests, execute::
python setup.py test
It is a good idea to enable C assertions as shown above under
`Build configuration`_.
Authors
-------
The principal developer of Tinyarray is Christoph Groth (CEA
Grenoble). His contributions are part of his work at `CEA <http://cea.fr/>`_,
the French Commissariat à l'énergie atomique et aux énergies alternatives.
The author can be reached at christoph.groth@cea.fr.
Other people that have contributed to Tinyarray include
* Michael Wimmer (Leiden University, TU Delft)
* Joseph Weston (CEA Grenoble, TU Delft)
* Jörg Behrmann (FU Berlin)
|