 
   describe 'minus() function', ->
 
-    it 'subtrats two matrices to a new one', ->
+    it 'subtrats two matrices to a new matrix', ->
       B = A2.clone()
       B2 = A.clone()
       C = B.minus(B2) # tested function


  describe 'transp() function', ->

    it 'transposes a matrix to a new one', ->
      B = A.clone()
      C = B.transp() # tested function
      expect(C).toEqual M [ 1, 2

      expect(B).toEqual A2_A # source unchanged ?
      expect(B2).toEqual A

    it 'adds two matrices to the second matrix', ->
      B = A2_A.clone()
      B2 = A.clone()
      C = B.add(B2, B2) # tested function
