We are starting to use Eigen for our Linear Algebra fonction. Se far we are very happy with Eigen library.

One problem came when I tried to reverse engineer the code using a UML tools for our design purpose. To my surprise I didn't find in the model the Vector2D or similar entities..

The problems root cause is the (ab)use of macro to simplify the typedef definition.

As a coder myself, I know that macro may be usefull for uniformization purpose or to solve some cross-compiler issues. But in that case:

Code: Select all

#define EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, Size, SizeSuffix)   \
/** \ingroup matrixtypedefs */                                    \
typedef Matrix<Type, Size, Size> Matrix##SizeSuffix##TypeSuffix;  \
/** \ingroup matrixtypedefs */                                    \
typedef Matrix<Type, Size, 1>    Vector##SizeSuffix##TypeSuffix;  \
/** \ingroup matrixtypedefs */                                    \
typedef Matrix<Type, 1, Size>    RowVector##SizeSuffix##TypeSuffix;

The use of macro is that case is only required to generate appropriate typedef.

What I'm proposing is that you should consider to expand typedef manually instead of letting the compiler doing so automatically. There is no overhead by doing so, unless the few minutes required for a programmer to do it. Those few minutes taken by a single programmer could save hours totaled over all the community when facing problems related to the use of unrequired macro.

Note that it is because I use the library that I took the time to post here. My goal is to be constructive in my remarks and suggestion. Also note that this is not a major issue for us and as long as Eigen fits our needs we will continue to use it.