merges r24969 from trunk into ruby_1_9_1, and adds a test for the fix.

--
* lib/matrix.rb (Matrix#rank): Two bug fixes. One made
  Matrix[[0,0],[0,0],[1,0]].rank raise a NoMethodError while the other
  one had Matrix[[0,1],[0,0],[1,0]].rank raise a TypeError.

git-svn-id: http://svn.ruby-lang.org/repos/ruby/branches/ruby_1_9_1@25708 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/matrix.rb b/lib/matrix.rb
index 88ccbca6b..04616d00d 100644
--- a/lib/matrix.rb
+++ b/lib/matrix.rb
@@ -776,7 +776,7 @@ class Matrix
         i = k
         exists = true
         loop do
-          if (i += 1) > a_column_size - 1
+          if (i += 1) > a_row_size - 1
             exists = false
             break
           end
@@ -789,14 +789,14 @@ class Matrix
           i = k
           exists = true
           loop do
-            if (i += 1) > a_row_size - 1
+            if (i += 1) > a_column_size - 1
               exists = false
               break
             end
             break unless a[k][i] == 0
           end
           if exists
-            k.upto(a_column_size - 1) do |j|
+            k.upto(a_row_size - 1) do |j|
               a[j][k], a[j][i] = a[j][i], a[j][k]
             end
             akk = a[k][k]