Abstract: An electronic calculator having a graph displaying function is adapted so that when a display range along only one coordinate axis is specified, an optimum display range for the other coordinate axis is automatically determined for displaying a graph within the display ranges. The remainder of the graph other than the portion thereof presented on the graph display is shown from portion to portion by scrolling along the trace of the graph in accordance with the result of the calculation being performed to determine the remainder. All of the data in a random access memory (RAM) can be transferred to an external device for the protection of the data when the device is connected to the calculator.