Abstract: A display system for a compact electronic apparatus uses a multi-level display means with a plurality of display lines. When the result of a computation is not displayed, all these display lines are available for displaying a computation expression. When the result of a computation is desired, that portion of the expression on the line on which the result of the computation is displayed is cleared. As a result, the user may be able to see the entire expression at a single glance and distinction between the expression and the result of the computation is clear so as to prevent misrecognition by the user.

Abstract: An electronic apparatus such as a compact computer stores a certain set of information which is useful in its operation such as a list of character codes and corresponding characters or the names of commands that can be used and the methods of using them. Such information can be displayed by entering a specified command or a character string with one or more characters, including a help requesting key.

Abstract: An electronic calculator having a first input mode for inputting one or more algebraic equations, a display for displaying the variable terms of the input equations, and an indicator for selectively indicating any one of the variables being displayed. A second input mode is provided for inputting numeric data in a direct one-to-one relationship with the displayed variables, the input numeric data being simultaneously displayed with their corresponding variables. A calculator operation is performed by the device upon instruction by an operator whereby the input numeric data is substituted for the respective input variables for a selected equation. The display will show the result of the calculation in a position of the display corresponding to the position where an output variable term is displayed. Accordingly, a numerical calculation may be performed by selecting a stored equation and directly inputting numeric data in a one-to-one correspondence with variables in the displayed selected equation.