PURPOSE: To draw the name and arrow of data in an irreducibly minimum area in the case of drawing a data flow diagram with a CASE tool.

CONSTITUTION: When an input position 35 of the data name is designated, the range of the data name expressed with the four points of upper left, lower left, upper right and lower right positions is calculated from the coordinate of the input position 35, the number of characters, the longitudinal size of one character and the lateral size, and the calculated range is stored. When a starting point 37 of the arrow is designated, the coordinate is stored. When an ending point 38 of the arrow is designated, the coordinate is stored. The starting point 37 and the lower left point in the range of the data name are connected by a straight line, the lower left point in the range of the data name and the lower right point are connected by a straight line, and the lower right point in the range of the data name and the ending point 38 of the arrow are connected by the straight line of the arrow.