eigen/doc/I14_PreprocessorDirectives.dox
Jitse Niesen dd232e30b0 Document QuaternionBase, minor doc improvements.
* Document class QuaternionBase so that docs for members are displayed.
* Remove obsolete \redstar refering to Array module
* Fix typo in Constants.h
* Document EIGEN_NO_AUTOMATIC_RESIZING
2011-12-08 14:22:06 +00:00

106 lines
6.5 KiB
Plaintext

namespace Eigen {
/** \page TopicPreprocessorDirectives Preprocessor directives
You can control some aspects of %Eigen by defining the preprocessor tokens using \c \#define. These macros
should be defined before any %Eigen headers are included. Often they are best set in the project options.
This page lists the preprocesor tokens recognised by %Eigen.
<b>Table of contents</b>
- \ref TopicPreprocessorDirectivesMajor
- \ref TopicPreprocessorDirectivesAssertions
- \ref TopicPreprocessorDirectivesPerformance
- \ref TopicPreprocessorDirectivesPlugins
- \ref TopicPreprocessorDirectivesDevelopers
\section TopicPreprocessorDirectivesMajor Macros with major effects
- \b EIGEN2_SUPPORT - if defined, enables the Eigen2 compatibility mode. This is meant to ease the transition
of Eigen2 to Eigen3 (see \ref Eigen2ToEigen3). Not defined by default.
- \b EIGEN2_SUPPORT_STAGEnn_xxx (for various values of nn and xxx) - staged migration path from Eigen2 to
Eigen3; see \ref Eigen2SupportModes.
- \b EIGEN_DEFAULT_TO_ROW_MAJOR - when defined, the default storage order for matrices becomes row-major
instead of column-major. Not defined by default.
- \b EIGEN_DEFAULT_DENSE_INDEX_TYPE - the type for column and row indices in matrices, vectors and array
(DenseBase::Index). Set to \c std::ptrdiff_t by default.
- \b EIGEN_DEFAULT_IO_FORMAT - the IOFormat to use when printing a matrix if no #IOFormat is specified.
Defaults to the #IOFormat constructed by the default constructor IOFormat().
- \b EIGEN_INITIALIZE_MATRICES_BY_ZERO - if defined, all entries of newly constructed matrices and arrays are
initializes to zero, as are new entries in matrices and arrays after resizing. Not defined by default.
- \b EIGEN_NO_AUTOMATIC_RESIZING - if defined, the matrices (or arrays) on both sides of an assignment
<tt>a = b</tt> have to be of the same size; otherwise, %Eigen automatically resizes \c a so that it is of
the correct size. Not defined by default.
\section TopicPreprocessorDirectivesAssertions Assertions
The %Eigen library contains many assertions to guard against programming errors, both at compile time and at
run time. However, these assertions do cost time and can thus be turned off.
- \b EIGEN_NO_DEBUG - disables %Eigen's assertions if defined. Not defined by default, unless the
\c NDEBUG macro is defined (this is a standard C++ macro which disables all asserts).
- \b EIGEN_NO_STATIC_ASSERT - if defined, compile-time static assertions are replaced by runtime assertions;
this saves compilation time. Not defined by default.
- \b eigen_assert - macro with one argument that is used inside %Eigen for assertions. By default, it is
basically defined to be \c assert, which aborts the program if the assertion is violated. Redefine this
macro if you want to do something else, like throwing an exception.
\section TopicPreprocessorDirectivesPerformance Alignment, vectorization and performance tweaking
- \b EIGEN_DONT_ALIGN - disables alignment completely. %Eigen will not try to align its objects and does not
expect that any objects passed to it are aligned. This will turn off vectorization. Not defined by default.
- \b EIGEN_DONT_ALIGN_STATICALLY - disables alignment of arrays on the stack. Not defined by default, unless
\c EIGEN_DONT_ALIGN is defined.
- \b EIGEN_DONT_VECTORIZE - disables explicit vectorization when defined. Not defined by default, unless
alignment is disabled by %Eigen's platform test or the user defining \c EIGEN_DONT_ALIGN.
- \b EIGEN_FAST_MATH - enables some optimizations which might affect the accuracy of the result. The only
optimization this currently includes is single precision sin() and cos() in the present of SSE
vectorization. Defined by default.
- \b EIGEN_UNROLLING_LIMIT - defines the size of a loop to enable meta unrolling. Set it to zero to disable
unrolling. The size of a loop here is expressed in %Eigen's own notion of "number of FLOPS", it does not
correspond to the number of iterations or the number of instructions. The default is value 100.
\section TopicPreprocessorDirectivesPlugins Plugins
It is possible to add new methods to many fundamental classes in %Eigen by writing a plugin. As explained in
the section \ref ExtendingMatrixBase, the plugin is specified by defining a \c EIGEN_xxx_PLUGIN macro. The
following macros are supported; none of them are defined by default.
- \b EIGEN_ARRAY_PLUGIN - filename of plugin for extending the Array class.
- \b EIGEN_ARRAYBASE_PLUGIN - filename of plugin for extending the ArrayBase class.
- \b EIGEN_CWISE_PLUGIN - filename of plugin for extending the Cwise class.
- \b EIGEN_DENSEBASE_PLUGIN - filename of plugin for extending the DenseBase class.
- \b EIGEN_DYNAMICSPARSEMATRIX_PLUGIN - filename of plugin for extending the DynamicSparseMatrix class.
- \b EIGEN_MATRIX_PLUGIN - filename of plugin for extending the Matrix class.
- \b EIGEN_MATRIXBASE_PLUGIN - filename of plugin for extending the MatrixBase class.
- \b EIGEN_PLAINOBJECTBASE_PLUGIN - filename of plugin for extending the PlainObjectBase class.
- \b EIGEN_QUATERNIONBASE_PLUGIN - filename of plugin for extending the QuaternionBase class.
- \b EIGEN_SPARSEMATRIX_PLUGIN - filename of plugin for extending the SparseMatrix class.
- \b EIGEN_SPARSEMATRIXBASE_PLUGIN - filename of plugin for extending the SparseMatrixBase class.
- \b EIGEN_SPARSEVECTOR_PLUGIN - filename of plugin for extending the SparseVector class.
- \b EIGEN_TRANSFORM_PLUGIN - filename of plugin for extending the Transform class.
- \b EIGEN_FUNCTORS_PLUGIN - filename of plugin for adding new functors and specializations of functor_traits.
\section TopicPreprocessorDirectivesDevelopers Macros for Eigen developers
These macros are mainly meant for people developing %Eigen. However, they can also be useful for power users
and the curious.
- \b EIGEN_INTERNAL_DEBUGGING - if defined, enables assertions in %Eigen's internal routines. This is useful
for debugging %Eigen itself. Not defined by default.
- \b EIGEN_NO_MALLOC - if defined, any request from inside the %Eigen to allocate memory from the heap
results in an assertion failure. This is useful to check that some routine does not allocate memory
dynamically. Not defined by default.
- \b EIGEN_RUNTIME_NO_MALLOC - if defined, a new switch is introduced which can be turned on and off by
calling <tt>set_is_malloc_allowed(bool)</tt>. If malloc is not allowed and %Eigen tries to allocate memory
dynamically anyway, an assertion failure results. Not defined by default.
*/
}