including eigen submodule in cmakelists, restructure

CMakeLists.txt

@@ -46,36 +46,43 @@ endif()
 ## then AUTODIFF
 
 if (USE_AUTODIFF)
-    message("-- Trying to find autodiff. Turn off via setting 'USE_AUTODIFF=OFF' in your environment before installation. ")
-    find_package(autodiff)
-    if (autodiff_FOUND)         
-        message("-- global installation of the autodiff library found: attempting to find Eigen3.")
-    else() 
-    message("-- no global installation of autodiff library found. Trying to include it as a submodule.")
-        set(INTERNAL_findautodiff_DIR ${PROJECT_SOURCE_DIR}/extern/autodiff)
-        if(NOT EXISTS ${INTERNAL_findautodiff_DIR})
-            message("The autodiff submodule was not found! Please run 'git submodule update --init'. Alternatively you can install autodiff globally on your system." )
+
+
+    find_package(Eigen3 REQUIRED NO_MODULE)
+    if(NOT Eigen3_FOUND)
+        message("-- Could not find Eigen3 library globally! Trying to include it as a submodule.")
+        set(EIGEN_PATH ${PROJECT_SOURCE_DIR}/extern/Eigen)
+        if(NOT EXISTS ${EIGEN_PATH})
+            message("The Eigen3 submodule was not found! Please run 'git submodule update --init'. Alternatively you can try to set the EIGEN_PATH to the eigen header files manually. Will proceed without autodiiferentiation." )
             set(USE_AUTODIFF OFF) 
         else()
-            add_subdirectory(${INTERNAL_findautodiff_DIR})
-            message("-- autodiff library found as a submodule. Tests will be compiled.")
-            set(autodiff_FOUND ON) 
+            message("-- Eigen3 library found as a submodule. Tests will be compiled.")
+            set(Eigen3_FOUND ON) 
         endif()
+    else()
+        message("-- Eigen3 library at ${EIGEN_PATH} found.")
     endif()
 
-    if (autodiff_FOUND)   
-
-        find_package(Eigen3 REQUIRED NO_MODULE)
+    if (Eigen3_FOUND)
 
         set(autodiff_INCLUDE_DIRS ${EIGEN_PATH})
 
-        if(NOT Eigen3_FOUND)
-            message("-- Could not find the Eigen3 library! Autodifferention disabled.")
-        else()
-            message("-- Eigen3 library found: Autodifferention enabled.")
-    endif()
-    else()
-        message("-- Could not find the autodiff library! Autodifferention disabled.")
+        message("-- Trying to find autodiff. Turn off via setting 'USE_AUTODIFF=OFF' in your environment before installation. ")
+        find_package(autodiff)
+        if (autodiff_FOUND)         
+            message("-- global installation of the autodiff library found: attempting to find Eigen3.")
+        else() 
+        message("-- no global installation of autodiff library found. Trying to include it as a submodule.")
+            set(INTERNAL_findautodiff_DIR ${PROJECT_SOURCE_DIR}/extern/autodiff)
+            if(NOT EXISTS ${INTERNAL_findautodiff_DIR})
+                message("The autodiff submodule was not found! Please run 'git submodule update --init'. Alternatively you can install autodiff globally on your system." )
+                set(USE_AUTODIFF OFF) 
+            else()
+                add_subdirectory(${INTERNAL_findautodiff_DIR})
+                message("-- autodiff library found as a submodule. Tests will be compiled.")
+                set(autodiff_FOUND ON) 
+            endif()
+        endif()
     endif()
 else()
     set(autodiff_FOUND OFF)