code: def matrix2sheet(self,float_row,float_col):
          
          xoffset = float_col*self.__xstep
          if isinstance(self.lbrt[0], datetime_types):
              xoffset = np.timedelta64(int(round(xoffset)), self._time_unit)
          x = self.lbrt[0] + xoffset
          yoffset = float_row*self.__ystep
          if isinstance(self.lbrt[3], datetime_types):
              yoffset = np.timedelta64(int(round(yoffset)), self._time_unit)
          y = self.lbrt[3] - yoffset
          return x, y
docs: Convert a floating-point location (float_row,float_col) in
          matrix coordinates to its corresponding location (x,y) in
          sheet coordinates.
  
          Valid for scalar or array float_row and float_col.
  
          Inverse of sheet2matrix().