r9529 - in /1.3: maths_fns/rotation_matrix.py test_suite/unit_tests/_maths_fns/test_rotation_matrix.py -- September 18, 2009 - 14:28

Author: bugman
Date: Fri Sep 18 14:28:37 2009
New Revision: 9529

URL: http://svn.gna.org/viewcvs/relax?rev=9529&view=rev
Log:
Created axis_angle_to_euler_zyz().

The test_euler_zyz_to_euler_zyz() unit test now checks both 
euler_zyz_to_axis_angle() and
axis_angle_to_euler_zyz().


Modified:
    1.3/maths_fns/rotation_matrix.py
    1.3/test_suite/unit_tests/_maths_fns/test_rotation_matrix.py

Modified: 1.3/maths_fns/rotation_matrix.py
URL: 
http://svn.gna.org/viewcvs/relax/1.3/maths_fns/rotation_matrix.py?rev=9529&r1=9528&r2=9529&view=diff
==============================================================================
--- 1.3/maths_fns/rotation_matrix.py (original)
+++ 1.3/maths_fns/rotation_matrix.py Fri Sep 18 14:28:37 2009
@@ -27,6 +27,30 @@
 from random import gauss, uniform
 
 
+def axis_angle_to_euler_zyz(axis, angle):
+    """Calculate the z-y-z Euler angles from the given axis-angle.
+
+    This first generates a rotation matrix via axis_angle_to_R() and then 
used this together with
+    R_to_euler_zyz() to obtain the Euler angles.
+
+    @param axis:    The 3D rotation axis.
+    @type axis:     numpy array, len 3
+    @param angle:   The rotation angle.
+    @type angle:    float
+    @return:        The alpha, beta, and gamma Euler angles in the z-y-z 
convention.
+    @rtype:         float, float, float
+    """
+
+    # Init.
+    R = zeros((3, 3), float64)
+
+    # Get the rotation.
+    axis_angle_to_R(axis, angle, R)
+
+    # Return the Euler angles.
+    return R_to_euler_zyz(R)
+
+
 def axis_angle_to_R(axis, angle, R):
     """Generate the rotation matrix from the axis-angle notation.
 

Modified: 1.3/test_suite/unit_tests/_maths_fns/test_rotation_matrix.py
URL: 
http://svn.gna.org/viewcvs/relax/1.3/test_suite/unit_tests/_maths_fns/test_rotation_matrix.py?rev=9529&r1=9528&r2=9529&view=diff
==============================================================================
--- 1.3/test_suite/unit_tests/_maths_fns/test_rotation_matrix.py (original)
+++ 1.3/test_suite/unit_tests/_maths_fns/test_rotation_matrix.py Fri Sep 18 
14:28:37 2009
@@ -244,6 +244,11 @@
         # 8) Rotation matrix to Euler angles.
         alpha_new, beta_new, gamma_new = R_to_euler_zyz(R)
 
+        # 9) Euler angles to axis-angle.
+        axis, angle = euler_zyz_to_axis_angle(alpha_new, beta_new, gamma_new)
+
+        # 10) Axis-angle to Euler angles.
+        alpha_new, beta_new, gamma_new = axis_angle_to_euler_zyz(axis, angle)
 
         # Wrap the angles.
         alpha_new = wrap_angles(alpha_new, 0, 2*pi)