EVAL
                       (c) 1993 by Alexander Walter



WHAT IS IT?
===========

    EVAL is a mathematical expression evaluator for QuickBasic. The
    expression must be in correct QuickBasic syntax, and can include
    functions such as SQR(), ATN(), COS(), etc. Correct hierarchy of
    mathematical evaluation is observed. Format of the result is decimal
    by default, but can be made hexadecimal or octal.


REGISTRATION INFORMATION
========================

    EVAL is offered as shareware. For a very modest $15 registration fee,
    you will receive the QuickBasic source code for EVAL. By registering,
    you can incorporate this sort of function into your Basic programs.
    Register by sending check or money order to:

         Alexander Walter
         182 ILER Dr.
         Middletown, NJ.  07748

         (800) 262-0827   USA only
         (908) 949-0507  or  (908) 671-5080   otherwise


USING EVAL
==========

    EVAL reads the command-line, and evaluates it as a valid QuickBasic
    mathematics expression. The syntax for using EVAL is:

                            eval <expression$>

    where <expression$> is a mathematical formula in QuickBasic syntax.
    For instance, the following are recognized and evaluated:

         eval 5 * sqr(30)
         eval 10 * log10(0.05)
         eval cos(pi/8)
         eval sqr(5.6e+3)
         eval hex$(32 + &h100)
         eval oct$(64 + &o777)
         eval 19.93 * (1.05^(-1/3) - 1)
         eval sinh(sinh(sinh(.01)))

    EVAL honors the algebraic operator hierarchy. At equal levels of
    parentheses nesting, algebraic operators are evaluated in the
    following order:

         ^    exponentiation
         -    negation
         *,/  multiplication and division
         \    integer division
         MOD  modulo arithmetic
         +,-  addition and subtraction
         Logical operations:  NOT, AND, OR, XOR, EQV, IMP

    Relational operations ( =, >, <, <>, <=, >= ) are not presently
    supported.


    Eval recognizes the following intrinsic QuickBasic functions:

         SIN()          COS()       ATN()       SQR()       ABS()
         INT()          LOG()       SGN()       TAN()       CINT()
         EXP()          MOD         AND         OR          XOR
         IMP            EQV

    The following mathematical functions are also evaluated by EVAL, even
    though they are not intrinsic QuickBasic functions. In the source
    code, registered users can easily see how to add more functions.

         SINH():        Hyperbolic sine
         COSH():        Hyperbolic cosine
         ARCSIN():      Arc sine
         ARCCOS():      Arc cosine
         LOG10():       Base 10 logarithm

    All sinusoidal functions are evaluated in radians.

    The following symbolic constants are also understood by EVAL. In the
    source code, registered users can easily see how to add recognition of
    other symbolic constants.

         PI = 3.141592653589793#

    Numeric constants are interpreted as decimal by default, but they can
    be interpreted as hexadecimal by prefixing the constant with "&h".
    Constants can be interpreted as octal by prefixing them with "&o". For
    instance, 65 = &h41 = &o101. The different representations can be
    mixed in the same expression.

    The format of the output is decimal by default, but can be made
    hexadecimal by enclosing the expression with "hex$()". The format can
    be made octal by enclosing the expression with "oct$()". For instance:

         COMMAND                    RESULT
         ---------                  ---------
         eval 65+65                 130
         eval hex$(65 + &o101)       82 (hex)
         eval oct$(&h41 + &o101)    202 (octal)

    With hexadecimal or octal output formatting, any fractional part of
    the result is truncated.


MISCELLANEOUS NOTES
===================

    If you are using the 4DOS replacement for Microsoft's COMMAND.COM,
    4DOS appears to interpret the exponentiation symbol "^", and prevents
    it from being passed to EVAL. For this reason, the tilde character "~"
    is also recognized as an exponentiation symbol.

    EVAL does not process statements that have adjacent exponentiation and
    negation, such as "4^-2". Instead, use parentheses such as "4^(-2)".


OTHER SHAREWARE PRODUCTS AVAILABLE:
==================================

    FONTEDIT:
    --------
    View & edit any HP LaserJet bit-mapped soft font. Requires
    VGA/EGA/CGA/Herc or AT&T video. Mouse optional. Handles portrait or
    landscape, fixed or proportional, and can convert between them.
    Handles up to 110 pt (VGA), 80 pt (EGA), 88 pt (Herc & AT&T), or 44 pt
    (CGA). Sculpt individual pixels, or use the many built-in special
    effects and area shapes. Can import characters from black & white
    .PCX, .TIF, or from other soft fonts. Many features.

    TT2BMAP:
    -------
    This program can convert a TrueType font into bitmapped, so that older
    DOS programs that don't understand TrueType can still use the latest
    fonts.