Handling Text Strings

A text string (plotted by command LABEL or DRAW TEXT) can include the escape character ``$\backslash$'' which is used to generate superscripts and subscripts and to monitor the font used. This escape character may be used in 2 ways

        \\X - set mode X until other mode change sequence
        \X  - set mode X for next character only

where X can be any of the following values and causes the following actions :

        N - Switch to current default character set
        1 - Switch to Simplex character set
        2 - Switch to Duplex character set         
        R - Roman font
        G - Greek font
        S - Script font
        I - Toggle italics
        U - Increase superscript/subscript level (move Up)
        D - Decrease superscript/subscript level (move Down)
        B - Backspace over previous character

Superscript and subscripts are handled using a ``level'' philosophy. $\backslash$U increases the level by 1, $\backslash$D decreases it by 1 and the size of the characters is (0.7)**ABS(level) times the current defined size. The italic mode is toggled by the $\backslash$I escape code. The character size is defined using command SET CHARACTER.