PCA: fixed scaling

1 files changed, 7 insertions, 5 deletions

diff --git a/transform.rb b/transform.rb
index 15d1f09..3c3b2da 100644
--- a/transform.rb
+++ b/transform.rb
@@ -24,10 +24,11 @@ class TransformTest < Test::Unit::TestCase
   
   def test_pca
   
-    d = GSL::Matrix.alloc([1,1.1,2,1.9,3,3.3], 3, 2)
-    td = GSL::Matrix.alloc([-1.64373917483226, -0.155542754209564, 1.79928192904182],3,1)
+    d = GSL::Matrix.alloc([1.0, -5, 1.1, 2.0, -5, 1.9, 3.0, -5, 3.3], 3, 3) # 2nd col is const -5, gets removed
+    rd = GSL::Matrix.alloc([1.0, 1.1, 1.9, 2.0, 3.1, 3.2], 3, 2)
+
+    td = GSL::Matrix.alloc([-1.4142135623731, -0.14142135623731, 1.5556349186104],3,1)
     ev = GSL::Matrix.alloc([0.707106781186548, 0.707106781186548], 2, 1)
-    rd = GSL::Matrix.alloc([1.05098674493306, 1.043223563717, 1.91019734898661, 2.0, 3.03881590608033, 3.256776436283], 3, 2)
   
     # Lossy
     2.times do # repeat to ensure idempotency
@@ -39,7 +40,8 @@ class TransformTest < Test::Unit::TestCase
       assert_equal pca.restore, rd
     end
   
-    td = GSL::Matrix.alloc([-1.64373917483226, 0.0883116327366195, -0.155542754209564, -0.155542754209564, 1.79928192904182, 0.0672311214729441],3,2)
+    rd = GSL::Matrix.alloc([1.0, 1.1, 2.0, 1.9, 3.0, 3.3], 3, 2) # 2nd col of d is const -5, gets removed on rd
+    td = GSL::Matrix.alloc([-1.4142135623731, -7.84962372879505e-17, -0.14142135623731, -0.14142135623731, 1.5556349186104, 0.141421356237309],3,2)
     ev = GSL::Matrix.alloc([0.707106781186548, -0.707106781186548, 0.707106781186548, 0.707106781186548], 2, 2)
   
     # Lossless
@@ -49,7 +51,7 @@ class TransformTest < Test::Unit::TestCase
       assert_equal pca.data_transformed_matrix, td
       assert_equal pca.transform(d), td
       assert_equal pca.eigenvector_matrix, ev
-      assert_equal pca.restore, d
+      assert_equal pca.restore, rd
     end
   
   end