code: function () {
              var tmp, a = this.val;
  
              tmp = a[1];
              a[1] = a[3];
              a[3] = tmp;
              tmp = a[2];
              a[2] = a[6];
              a[6] = tmp;
              tmp = a[5];
              a[5] = a[7];
              a[7] = tmp;
  
              return this;
          }
docs: Transpose the value of this matrix.
  @name transpose
  @memberOf me.Matrix2d
  @function
  @return {me.Matrix2d} Reference to this object for method chaining