* lib/matrix.rb: Fix sign for cross_product [#9499]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46780 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/matrix.rb b/lib/matrix.rb
index 1a7519f408..026492b6b8 100644
--- a/lib/matrix.rb
+++ b/lib/matrix.rb
@@ -1811,9 +1811,9 @@ class Vector
   #
   def cross_product(v)
     Vector.Raise ErrDimensionMismatch unless size == v.size && v.size == 3
-    Vector[ v[1]*@elements[2] - v[2]*@elements[1],
-            v[2]*@elements[0] - v[0]*@elements[2],
-            v[0]*@elements[1] - v[1]*@elements[0] ]
+    Vector[ v[2]*@elements[1] - v[1]*@elements[2],
+            v[0]*@elements[2] - v[2]*@elements[0],
+            v[1]*@elements[0] - v[0]*@elements[1] ]
   end
 
   #