Introducing Eigen as git-submodule.
This allows for easy installation as no paths must be set and Eigen does not need to be downloaded manually by the user.
Eigen for some linear algebra operations
Eigen is automatically cloned as a git submodule. Therefore to activate Eigen, simply set the cmake variable
ON, e.g. via:
$ cmake ../hyteg -DHYTEG_BUILD_WITH_EIGEN=ON
CMake will automatically find the Eigen submodule, there is no need to specify a path or to download Eigen at all.
For now we decided to make "build with Eigen" optional and default to OFF.
However, it is cloned regardless with
The reason for that is to minimize compile time whenever possible (although Eigen
is a header-only library, some of our tests or apps are not built if Eigen is disabled).