+ /*\r
+ public override MatrixExpression this[Interval row, Interval col]\r
+ {\r
+ get\r
+ {\r
+ return new MatrixExpression(this, row.int_floor(), col.int_floor(), row.int_ceil(), col.int_ceil());\r
+ }\r
+ set\r
+ {\r
+ for(int r = 0, r<)\r
+ elements[row - 1, col - 1] = value;\r
+ }\r
+ }\r
+ * */\r
+\r
+ public override int rows { get { return elements.GetLength(0); } }\r
+ public override int cols { get { return elements.GetLength(1); } }\r
+\r