fix doc of Quaternion::setFromTwoVectors
diff --git a/Eigen/src/Geometry/Quaternion.h b/Eigen/src/Geometry/Quaternion.h
index d7480bf..f2ebece 100644
--- a/Eigen/src/Geometry/Quaternion.h
+++ b/Eigen/src/Geometry/Quaternion.h
@@ -342,11 +342,15 @@
return res;
}
-/** Sets *this to be a quaternion representing a rotation sending the vector \a a to the vector \a b.
+/** Sets \c *this to be a quaternion representing a rotation between
+ * the two arbitrary vectors \a a and \a b. In other words, the built
+ * rotation represent a rotation sending the line of direction \a a
+ * to the line of direction \a b, both lines passing through the origin.
*
- * \returns a reference to *this.
+ * \returns a reference to \c *this.
*
- * Note that the two input vectors do \b not have to be normalized.
+ * Note that the two input vectors do \b not have to be normalized, and
+ * do not need to have the same norm.
*/
template<typename Scalar>
template<typename Derived1, typename Derived2>
