Squashed 'third_party/eigen/' changes from 61d72f6..cf794d3
Change-Id: I9b814151b01f49af6337a8605d0c42a3a1ed4c72
git-subtree-dir: third_party/eigen
git-subtree-split: cf794d3b741a6278df169e58461f8529f43bce5d
diff --git a/unsupported/doc/examples/EulerAngles.cpp b/unsupported/doc/examples/EulerAngles.cpp
new file mode 100644
index 0000000..1ef6aee
--- /dev/null
+++ b/unsupported/doc/examples/EulerAngles.cpp
@@ -0,0 +1,46 @@
+#include <unsupported/Eigen/EulerAngles>
+#include <iostream>
+
+using namespace Eigen;
+
+int main()
+{
+ // A common Euler system by many armies around the world,
+ // where the first one is the azimuth(the angle from the north -
+ // the same angle that is show in compass)
+ // and the second one is elevation(the angle from the horizon)
+ // and the third one is roll(the angle between the horizontal body
+ // direction and the plane ground surface)
+ // Keep remembering we're using radian angles here!
+ typedef EulerSystem<-EULER_Z, EULER_Y, EULER_X> MyArmySystem;
+ typedef EulerAngles<double, MyArmySystem> MyArmyAngles;
+
+ MyArmyAngles vehicleAngles(
+ 3.14/*PI*/ / 2, /* heading to east, notice that this angle is counter-clockwise */
+ -0.3, /* going down from a mountain */
+ 0.1); /* slightly rolled to the right */
+
+ // Some Euler angles representation that our plane use.
+ EulerAnglesZYZd planeAngles(0.78474, 0.5271, -0.513794);
+
+ MyArmyAngles planeAnglesInMyArmyAngles = MyArmyAngles::FromRotation<true, false, false>(planeAngles);
+
+ std::cout << "vehicle angles(MyArmy): " << vehicleAngles << std::endl;
+ std::cout << "plane angles(ZYZ): " << planeAngles << std::endl;
+ std::cout << "plane angles(MyArmy): " << planeAnglesInMyArmyAngles << std::endl;
+
+ // Now lets rotate the plane a little bit
+ std::cout << "==========================================================\n";
+ std::cout << "rotating plane now!\n";
+ std::cout << "==========================================================\n";
+
+ Quaterniond planeRotated = AngleAxisd(-0.342, Vector3d::UnitY()) * planeAngles;
+
+ planeAngles = planeRotated;
+ planeAnglesInMyArmyAngles = MyArmyAngles::FromRotation<true, false, false>(planeRotated);
+
+ std::cout << "new plane angles(ZYZ): " << planeAngles << std::endl;
+ std::cout << "new plane angles(MyArmy): " << planeAnglesInMyArmyAngles << std::endl;
+
+ return 0;
+}