diff --git a/lib/matrix/matrix.rb b/lib/matrix/matrix.rb
index 250e054..20d902e 100644
--- a/lib/matrix/matrix.rb
+++ b/lib/matrix/matrix.rb
@@ -112,61 +112,17 @@ def self.convert(matrix)
       fast_matrix
     end
 
-    #
+   #
     # Yields all elements of the matrix, starting with those of the first row
     #
     #   Matrix[ [1,2], [3,4] ].each { |e| puts e }
     #     # => prints the numbers 1 to 4
-     def each(which = :all) # :yield: e
-        return to_enum :each, which unless block_given?
-        case which
-        when :all
-          (0...row_count).each do |i|
-            (0...column_count).each do |j|
-              yield self[i, j]
-            end
-          end
-        when :diagonal
-          (0...[row_count, column_count].min).each do |i|
-                yield self[i, i]
-          end
-        when :off_diagonal
-          (0...row_count).each do |i|
-            (0...column_count).each do |j|
-              if i != j
-                yield self[i, j]
-              end
-            end
-          end
-        when :lower
-          (0...row_count).each do |i|
-            (0..[i,column_count-1].min).each do |j|
-              yield self[i, j]
-            end
-          end
-        when :strict_lower
-          (1...row_count).each do |i|
-            (0...[i,column_count].min).each do |j|
-                yield self[i, j]
-            end
-          end
-        when :strict_upper
-          (0...row_count).each do |i|
-            (i+1...column_count).each do |j|
-              yield self[i, j]
-            end
-          end
-        when :upper
-          (0...row_count).each do |i|
-            (i...column_count).each do |j|
-              yield self[i, j]
-            end
-          end
-        else
-          raise ArgumentError, "expected #{which.inspect} to be one of :all, :diagonal, :off_diagonal, :lower, :strict_lower, :strict_upper or :upper"
-        end
-        self
+      def each(which = :all) # :yield: e
+        return to_enum :each, which unless block_given?        
+        
+        each_with_index(which){ |elem, _, _| yield elem}
       end
+
     #
     # Same as #each, but the row index and column index in addition to the element
     #
@@ -179,17 +135,85 @@ def each(which = :all) # :yield: e
     #     #    3 at 1, 0
     #     #    4 at 1, 1
     #
-    def each_with_index
-      raise NotSupportedError unless block_given?
+    def each_with_index(which = :all) # :yield: e, row, column
+      return to_enum :each_with_index, which unless block_given?
+      case which
+      when :all
+        each_all{|i, j| yield self[i, j], i, j}
+      when :diagonal
+        each_diagonal{|i, j| yield self[i, j], i, j}
+      when :off_diagonal
+        each_off_diagonal{|i, j| yield self[i, j], i, j}
+      when :lower
+        each_lower{|i, j| yield self[i, j], i, j}
+      when :strict_lower
+        each_strict_lower{|i, j| yield self[i, j], i, j}
+      when :strict_upper
+        each_strict_upper{|i, j| yield self[i, j], i, j}
+      when :upper
+        each_upper{|i, j| yield self[i, j], i, j}
+      else
+        raise ArgumentError, "expected #{which.inspect} to be one of :all, :diagonal, :off_diagonal, :lower, :strict_lower, :strict_upper or :upper"
+      end
+      self
+    end
 
+    def each_all(&block)
       (0...row_count).each do |i|
         (0...column_count).each do |j|
-          yield self[i, j], i, j
+          block[i,j]
         end
       end
-      self
     end
 
+    def each_diagonal(&block)
+      (0...[row_count, column_count].min).each do |i|
+        block[i, i]
+      end
+    end
+
+    def each_off_diagonal(&block)
+      (0...row_count).each do |i|
+        (0...column_count).each do |j|
+          if i != j
+            block[i, j]
+          end
+        end
+      end
+    end
+
+    def each_lower(&block)
+      (0...row_count).each do |i|
+        (0..[i,column_count-1].min).each do |j|
+          block[i, j]
+        end
+      end
+    end
+
+    def each_strict_lower(&block)
+      (1...row_count).each do |i|
+        (0...[i,column_count].min).each do |j|
+          block[i, j]
+        end
+      end
+    end
+
+    def each_strict_upper(&block)
+      (0...row_count).each do |i|
+        (i+1...column_count).each do |j|
+          block[i, j]
+        end
+      end
+    end
+
+    def each_upper(&block)
+      (0...row_count).each do |i|
+        (i...column_count).each do |j|
+          block[i, j]
+        end
+      end
+    end
+    
     # don't use (Issue#1)
     def each_with_index!
       (0...row_count).each do |i|
diff --git a/test/matrix/matrix_test.rb b/test/matrix/matrix_test.rb
index 357aa9a..d5d0a0a 100644
--- a/test/matrix/matrix_test.rb
+++ b/test/matrix/matrix_test.rb
@@ -259,6 +259,121 @@ def test_each_strict_upper_rec2
       assert_equal [2, 3, 6], m.each(:strict_upper).to_a 
     end
     
+    def test_each_wi_all_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[1.0, 0, 0], [2.0, 0, 1], [3.0, 1, 0], [4.0, 1, 1]], m.each_with_index(:all).to_a
+    end
+
+    def test_each_wi_all_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[1.0, 0, 0], [2.0, 0, 1], [3.0, 1, 0], [4.0, 1, 1], [5.0, 2, 0], [6.0, 2, 1]], m.each_with_index(:all).to_a
+    end
+
+    def test_each_wi_all_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[1.0, 0, 0], [2.0, 0, 1], [3.0, 0, 2], [4.0, 1, 0], [5.0, 1, 1], [6.0, 1, 2]], m.each_with_index(:all).to_a
+    end
+
+    def test_each_wi_diagonal_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[1.0, 0, 0], [4.0, 1, 1]], m.each_with_index(:diagonal).to_a
+    end
+
+    def test_each_wi_diagonal_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[1.0, 0, 0], [4.0, 1, 1]], m.each_with_index(:diagonal).to_a
+    end
+
+    def test_each_wi_diagonal_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[1.0, 0, 0], [5.0, 1, 1]], m.each_with_index(:diagonal).to_a
+    end
+
+    def test_each_wi_off_diagonal_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[2.0, 0, 1], [3.0, 1, 0]], m.each_with_index(:off_diagonal).to_a
+    end
+
+    def test_each_wi_off_diagonal_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[2.0, 0, 1], [3.0, 1, 0], [5.0, 2, 0], [6.0, 2, 1]], m.each_with_index(:off_diagonal).to_a
+    end
+
+    def test_each_wi_off_diagonal_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[2.0, 0, 1], [3.0, 0, 2], [4.0, 1, 0], [6.0, 1, 2]], m.each_with_index(:off_diagonal).to_a
+    end
+
+    def test_each_wi_lower_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[1.0, 0, 0], [3.0, 1, 0], [4.0, 1, 1]], m.each_with_index(:lower).to_a
+    end
+
+    def test_each_wi_lower_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[1.0, 0, 0], [3.0, 1, 0], [4.0, 1, 1], [5.0, 2, 0], [6.0, 2, 1]], m.each_with_index(:lower).to_a
+    end
+
+    def test_each_wi_lower_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[1.0, 0, 0], [4.0, 1, 0], [5.0, 1, 1]], m.each_with_index(:lower).to_a
+    end
+
+    def test_each_wi_strict_lower_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[3.0, 1, 0]], m.each_with_index(:strict_lower).to_a
+    end
+
+    def test_each_wi_strict_lower_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[3.0, 1, 0], [5.0, 2, 0], [6.0, 2, 1]], m.each_with_index(:strict_lower).to_a
+    end
+
+    def test_each_wi_strict_lower_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[4.0, 1, 0]], m.each_with_index(:strict_lower).to_a
+    end
+
+    def test_each_wi_upper_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[1.0, 0, 0], [2.0, 0, 1], [4.0, 1, 1]], m.each_with_index(:upper).to_a
+    end
+
+    def test_each_wi_upper_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[1.0, 0, 0], [2.0, 0, 1], [4.0, 1, 1]], m.each_with_index(:upper).to_a
+    end
+
+    def test_each_wi_upper_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[1.0, 0, 0], [2.0, 0, 1], [3.0, 0, 2], [5.0, 1, 1], [6.0, 1, 2]], m.each_with_index(:upper).to_a
+    end
+
+    def test_each_wi_strict_upper_sq
+      m = Matrix[[1, 2], [3, 4]]
+      assert_equal [[2.0, 0, 1]], m.each_with_index(:strict_upper).to_a
+    end
+
+    def test_each_wi_strict_upper_rec1
+      m = Matrix[[1, 2], [3, 4], [5, 6]]
+      assert_equal [[2.0, 0, 1]], m.each_with_index(:strict_upper).to_a
+    end
+
+    def test_each_wi_strict_upper_rec2
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_equal [[2.0, 0, 1], [3.0, 0, 2], [6.0, 1, 2]], m.each_with_index(:strict_upper).to_a
+    end
+    
+    def test_each_argument_error
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_raises (ArgumentError){ m.each(:al).to_a }
+    end  
+    
+     def test_each_wi_argument_error
+      m = Matrix[[1, 2, 3], [4, 5, 6]]
+      assert_raises (ArgumentError){ m.each_with_index(:al).to_a }
+    end  
+    
     def test_greater
       m1 = Matrix[[1, 2, 3], [3, 2, 1]]
       m2 = Matrix[[2, 3, 6], [4, 4, 4]]