From 2106aa1990a5b6a81c0883d8732741de51e449cd Mon Sep 17 00:00:00 2001
From: marcandre <marcandre@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Sat, 13 Apr 2013 03:08:28 +0000
Subject: * lib/matrix.rb: Add Vector#cross_product, patch by Luis Ezcurdia  
 [fix GH-276] [rubyspec:81eec89a124]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40273 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 lib/matrix.rb | 12 ++++++++++++
 1 file changed, 12 insertions(+)

(limited to 'lib/matrix.rb')

diff --git a/lib/matrix.rb b/lib/matrix.rb
index b1d1a5c2bd..9bda8855ce 100644
--- a/lib/matrix.rb
+++ b/lib/matrix.rb
@@ -1519,6 +1519,7 @@ end
 #
 # Vector functions:
 # * #inner_product(v)
+# * #cross_product(v)
 # * #collect
 # * #magnitude
 # * #map
@@ -1757,6 +1758,17 @@ class Vector
     p
   end
 
+  #
+  # Returns the cross product of this vector whit the other.
+  #   Vector[1, 0, 0].cross_product Vector[0, 1, 0]   => Vector[0, 0, 1]
+  #
+  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] ]
+  end
+
   #
   # Like Array#collect.
   #
-- 
cgit v1.2.3