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.. Copyright (c) 2016, Johan Mabille and Sylvain Corlay
Distributed under the terms of the BSD 3-Clause License.
The full license is in the file LICENSE, distributed with this software.
Basic usage
===========
Manipulating abstract batches
-----------------------------
Here is an example that computes the mean of two batches, using the best
architecture available, based on compile time informations:
.. literalinclude:: ../../test/doc/manipulating_abstract_batches.cpp
The batch can be a batch of 4 single precision floating point numbers (e.g. on
Neon) or a batch of 8 (e.g. on AVX2).
Manipulating parametric batches
-------------------------------
The previous example can be made fully parametric, both in the batch type and
the underlying architecture. This is achieved as described in the following
example:
.. literalinclude:: ../../test/doc/manipulating_parametric_batches.cpp
At its core, a :cpp:class:`xsimd::batch` is bound to the scalar type it contains, and to the
instruction set it can use to operate on its values.
Explicit use of an instruction set extension
--------------------------------------------
Here is an example that loads two batches of 4 double floating point values, and
computes their mean, explicitly using the AVX extension:
.. literalinclude:: ../../test/doc/explicit_use_of_an_instruction_set.cpp
Note that in that case, the instruction set is explicilty specified in the batch type.
This example outputs:
.. code::
(2.0, 3.0, 4.0, 5.0)
.. warning::
If you allow your compiler to generate AVX2 instructions (e.g. through
``-mavx2``) there is nothing preventing it from optimizing the above code
using AVX2 instructions.
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