1 files changed, 3 insertions, 3 deletions
diff --git a/lib/matrix.rb b/lib/matrix.rb
index a0f116095c..9d6650370d 100644
--- a/lib/matrix.rb
+++ b/lib/matrix.rb
@@ -983,11 +983,11 @@ class Matrix
   #
   def unitary?
     raise ErrDimensionMismatch unless square?
-    rows.each_with_index do |row, i|
-      column_count.times do |j|
+    rows.each_with_index do |row_i, i|
+      rows.each_with_index do |row_j, j|
         s = 0
         row_count.times do |k|
-          s += row[k].conj * rows[k][j]
+          s += row_i[k].conj * row_j[k]
         end
         return false unless s == (i == j ? 1 : 0)
       end