Use quaternions instead of 3*3 matrices to represent rotations.

1 files changed, 4 insertions, 4 deletions

diff --git a/org/madore/ephem/Nutation.java b/org/madore/ephem/Nutation.java
index dcfdc30..bc6e721 100644
--- a/org/madore/ephem/Nutation.java
+++ b/org/madore/ephem/Nutation.java
@@ -63,10 +63,10 @@ public final class Nutation {
 	return data.get(v);
     }
 
-    public static Frames.RotationMatrix matrix(double t) {
-	Frames.RotationMatrix mat1 = Frames.RotationMatrix.rotx(Precession.epsilon.v(t)*Comput.arcsecond);
-	Frames.RotationMatrix mat2 = Frames.RotationMatrix.rotz(-getFunc(Variable.PSI).v(t)*Comput.arcsecond).apply(mat1);
-	Frames.RotationMatrix mat3 = Frames.RotationMatrix.rotx(-(Precession.epsilon.v(t)+getFunc(Variable.EPSILON).v(t))*Comput.arcsecond).apply(mat2);
+    public static Frames.Rotation matrix(double t) {
+	Frames.Rotation mat1 = Frames.Rotation.rotx(Precession.epsilon.v(t)*Comput.arcsecond);
+	Frames.Rotation mat2 = Frames.Rotation.rotz(-getFunc(Variable.PSI).v(t)*Comput.arcsecond).apply(mat1);
+	Frames.Rotation mat3 = Frames.Rotation.rotx(-(Precession.epsilon.v(t)+getFunc(Variable.EPSILON).v(t))*Comput.arcsecond).apply(mat2);
 	return mat3;
     }