Abstract: It is an object of the invention to provide an electronic computing apparatus having an arithmetic processing function and an arithmetic processing method which allow an arithmetic expression to be readily inputted. A screen showing stored contents of an arithmetic expression menu table is displayed by specifying an arithmetic expression menu display command key. Then, selecting an arithmetic expression from the displayed plurality of arithmetic expressions by an input pen allows the selected arithmetic expression to be inputted. A controller executes arithmetic processing in accordance with the selected arithmetic expression and displays the result of the arithmetic processing as a graph on the display. Accordingly, the arithmetic expression may be readily inputted just by selecting the arithmetic expression from the predetermined plurality of arithmetic expressions.

Abstract: It is an object of the invention to solve problems with a calculator capable of displaying a graph of a function in that the characteristics of a graph displayed by inputting a function can not be recognized when a desired display range is not at an appropriate value and in that a value to change the display range has had to be input on a trial and error basis, which has made the operation very complicated. A calculator according to the invention displays a graph of a function on a reduced scale, further displays buttons for increasing and decreasing display ranges of an X-axis and a Y-axis around the graph and changes the graph of the function and displays it again in response to instructions by the user on the buttons. This makes it possible to correct the display ranges of the graph of the function easily.

Abstract: There are provided an electronic computing apparatus having a graph displaying function and a graph displaying method which allow an optimum graph to be quickly displayed. A graph is displayed on a display based on data for displaying the graph inputted from a key input section or the like. When one numeric key selected from among a plurality of numeric keys is specified by a predetermined number of times, a quadrant corresponding to the numeric key is selected from a quadrant selection table and a scale corresponding to the specified number of times is selected from a quadrant scale selection table, redisplaying a part of the graph existing in the selected quadrant on the selected scale. Thus, a desired graph may be quickly displayed by selecting the quadrant and scale of the displayed graph.

Abstract: A display for use in a computer, for example a word processor or a personal computer, includes a device for forming a help message on the display. The help message can provide help when an error occurs in operation. Also a help message can be provided for a current mode when a help key in depressed thus assisting the operators even though there is no error.

Abstract: A print control system for a word processing apparatus includes a character pattern data generation circuit and a background pattern data generation circuit. The character pattern data developed from the character pattern data generation circuit and the background pattern data developed from the background pattern data generation circuit are combined at an OR gate. A composite data signal developed from the OR gate is applied to a dot matrix printer, whereby the character pattern is superimposed on the background pattern in order to ornamentally emphasize the character pattern.