eigen3 missing error during ROS installation

Question

Hi I'm trying to install ROS on my MAC using homebrew.While installation I got this message :

 CMake Error at CMakeLists.txt:7 (find_package):
 By not providing "FindEigen3.cmake" in CMAKE_MODULE_PATH this project has
 asked CMake to find a package configuration file provided by "Eigen3", but
 CMake did not find one
 Could not find a package configuration file provided by "Eigen3" with any
 of the following names:
Eigen3Config.cmake
eigen3-config.cmake
Add the installation prefix of "Eigen3" to CMAKE_PREFIX_PATH or set
"Eigen3_DIR" to a directory containing one of the above files.  If "Eigen3"
provides a separate development package or SDK, be sure it has been
installed.
-- Configuring incomplete, errors occurred!
See also "/Users/Jishnu/ros_catkin_ws/build_isolated/pcl_ros/CMakeFiles/CMakeOutput.log".
<== Failed to process package 'pcl_ros': 
Command '['/Users/Jishnu/ros_catkin_ws/install_isolated/env.sh', ' cmake',      '/Users/Jishnu/ros_catkin_ws/src/perception_pcl/pcl_ros', '-  DCATKIN_DEVEL_PREFIX=/Users/Jishnu/ros_catkin_ws/devel_isolated/pcl_ros', '-DCMAKE_INSTALL_PREFIX=/Users/Jishnu/ros_catkin_ws/install_isolated', '-DCMAKE_BUILD_TYPE=Release', '-G', 'Unix Makefiles']' returned non-zero exit status 1

I'M a beginner in ROS, so could someone please help me out with this. I have checked if Eigen is installed, version 3.2.4 is already installed

Answer 1

This solved the problem for me.

It seems this has been resolved, but I'll share how I got this working: Elsewhere in the ros build workspace I found a copy of FindEigen3.cmake:

ros_catkin_ws$ cp src/orocos_kinematics_dynamics/orocos_kdl/config/FindEigen3.cmake
src/perception_pcl/pcl_ros/cfg/ Then I removed the following from CMakeLists:

find_package(Eigen 3 Required) Replacing it with these lines from the orocos CMakeLists

find_package(Eigen 3 QUIET) if(NOT Eigen_FOUND)
include(${PROJ_SOURCE_DIR}/cfg/FindEigen3.cmake)
set(Eigen_INCLUDE_DIR ${EIGEN3_INCLUDE_DIR}) endif() include_directories(${Eigen_INCLUDE_DIR}) To be perfectly honest, I didn't change config -> cfg when I did my build, but it seems to have worked.

Answer 2

What I did to solve such problem was:

• Finding the current value of CMAKE_ROOT by print it out using message( WARNING ${CMAKE_ROOT}) in .cmake file
• Make sure Modules/FindEigen3.cmake exists in that folder
• If not, download a copy from https://github.com/RainerKuemmerle/g2o/blob/master/cmake_modules/FindEigen3.cmake