U cannot put eigen3 from default system location

present CMakeList.txt cannot find eigen . U have to provide path of /use/local/include/gtsam/3rdparty/Eigen

this is custom Eigen lib of gtsam which builds all modules otherwise u get signature mismatch error while build.

Refer line 21 of this fork https://github.com/robotics-research-center/pygtsam/blob/master/CMakeLists.txt