r10078 - /1.3/maths_fns/rotation_matrix.py -- December 09, 2009 - 11:25

Author: bugman
Date: Wed Dec  9 11:25:58 2009
New Revision: 10078

URL: http://svn.gna.org/viewcvs/relax?rev=10078&view=rev
Log:
Fixed the problem case for R_to_euler_zxy().


Modified:
    1.3/maths_fns/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=10078&r1=10077&r2=10078&view=diff
==============================================================================
--- 1.3/maths_fns/rotation_matrix.py (original)
+++ 1.3/maths_fns/rotation_matrix.py Wed Dec  9 11:25:58 2009
@@ -1946,10 +1946,10 @@
     # The beta Euler angle.
     beta = asin(-R[1, 2])
 
-    # Problem case - beta is zero so alpha and gamma are indistinguishable.
-    if -R[1, 2] == 0.0:
+    # Problem case - beta is pi/2 so alpha and gamma are indistinguishable.
+    if beta == pi/2:
         # Put all the rotation into alpha.
-        alpha = atan2(-R[0, 1], -R[2, 1])
+        alpha = atan2(-R[0, 1], R[0, 0])
 
         # Gamma.
         gamma = 0.0