PLOT 3D

        Plot  3D is a general function plotting program for Windows  3.1. 
        It  calculates and plots values of z as any function of x and  y. 
        The  function z=f(x,y) can be edited and  immediately  displayed. 
        This  program is meant as a learning tool to give the student  an 
        intuitive feel for equations of one or two variables.
        
        The  program's engine is an interpreter that recognizes  standard 
        mathematical  infix notation. You may use variable  names,  which 
        may  be up to 32 characters long, to store  intermediate  values. 
        The  three  predefined variables "x", "y" and "z"  represent  the 
        function's  input  ("x"  and "y") and output  ("z")  values:  the 
        function  may use "x" and "y", which will vary over  a  specified 
        domain, to calculate and assign a value to "z".
        
        The interpreter recognizes the following unary and binary  opera-
        tions:
        
                - Negation
                ! Logical NOT
                ~ Binary NOT
        
                / Division
                * Multiplication
                % Modulo division
                + Addition
                - Subtraction
                << Shift left
                >> Shift right
                < Less than
                <= Less or equal
                > Greater than
                >= Greater or equal
                == Equality
                != Inequality
                & Binary AND
                | Binary exclusive OR
                ^ Binary inclusive OR
                && Logical AND
                || Logical OR
        
        Plot 3d provides the following functions and constants:
        
                abs(a) - absolute value
                acos(a) - arc cosine
                asin(a) - arc sine
                atan(a) - arc tangent
                atan2(a,b) - arc tangent
                ceil(a) - returns smallest integer not less than "a"
                cos(a) - cosine
                cosh(a) - hyperbolic cosine
                exp(a) - raise e to the power of "a"
                floor(a) returns largest integer not greater than "a"
                log(a) - natural log
                log10(a) - log base 10
                pow(a,b) - raise "a" to the power of "b"
                sin(a) - sine
                sinh(a) - hyperbolic sine
                sqrt(a) - square root
                tan(a) - tangent
                tanh(a) - hyperbolic tangent
        
                E -         2.71828182845904523536
                LOG2E -     1.44269504088896340736
                LOG10E -    0.434294481903251827651
                LN2 -       0.693147180559945309417
                LN10 -      2.30258509299404568402
                PI -        3.14159265358979323846
                PI_2 -      1.57079632679489661923
                PI_4 -      0.785398163397448309616
                SQRTPI -    0.564189583547756286948
                SQRT2 -     1.41421356237309504880
                SQRT_2 -    0.707106781186547524401
        
        In  addition  to the above functions, the program  also  supports 
        conditional and looping statements, similar to C syntax:
        
                if ( <condition> )
                        <statement>
                else
                        <statement>
        
                for ( <init>; <test>; <inc> )
                        <statement>
        
                while ( <condition> )
                        <statement>
        
        Have  fun! I hope you enjoy using this program as much as  I  had 
        writing it! If you have any questions or comments, please  direct 
        them to:
        
                Robert Brodt
                Chameleon Software, Inc.
                486 Linden Ave.
                Bogota, NJ 07603
                USA
        
                Compuserve ID 71165,550
                Tel.: (201) 488-9130