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: An electronic desk calculator includes: an input device for inputting a plurality of numeral units and an operator; a counter for storing a value representing the number of numeral units; a controller for performing a calculation based on at least one numeral unit and the operator, and for receiving the at least one numeral unit input through the input device to increase a value stored in the counter by one; and a display for displaying the value stored in the counter.