Club Amiga de Montreal - CAM/CAM_CD_1.iso/files/447.lha/Calc_v2.0/Calc.doc.pp/Calc.doc

Text File | 1990-12-08 | 19.0 KB | 397 lines

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    CALC 2.0    by Bill Dimm
           Amiga Version    August 7, 1990

         The Amiga version of Calc may be distributed freely as long as no
    charge beyond a reasonable copying fee is made.  This program is
    shareware - if you like it, you are encouraged to send me (a starving
    grad student :-) ) a donation.  If you have any bugs to report, or any
    requests for features for the next version, please send them also.

         Bill Dimm
         Box 385
         Springfield, PA. 19064-0385

         [e-mail]
         [e-mail]


    USAGE

         Usage1: CALC [options]
         Usage2: CALC [options] expression1 expression2 ...
         Usage3: CALC [options] -v var expression [file1 file2 ...]

    DESCRIPTION

         Calc is a shell style calculator.  Calc does not have a fancy
    keypad display as many other calculator programs do.  Instead, it is
    capable of taking its input from a file, the keyboard (stdin), or a
    command line and outputting its results to a file or the screen
    (stdout).  It can also apply a single equation to all of the values
    stored in a file (or files).  It handles all common mathematical
    expressions, can optionally predefine physical constants (see the
    options -m and -g and the commands mks and gaussian), and allows you to
    store values in the 26 variables a-z.
         If Calc is invoked using the format in Usage1, it will read
    mathematical expressions and commands from the keyboard or the input
    file (see option -i and command infile) and execute them until it
    encounters the exit command, or finds the end of the input file.  If
    Calc is reading from the keyboard, it will display a prompt CALC> when
    it is waiting for a command or mathematical expression.  The command or
    expression is evaluated when the return key is pressed.  Expressions
    may be of any length, and case is ignored.  The result of the
    evaluation of all mathematical expressions is displayed on the screen,
    or stored in a file (see option -o and the command outfile).  When an
    error occurs, an error message is printed to the screen, or to a file
    (see option -e and the command errorfile), and Calc ignores the rest of
    the line and continues (unless the error is critical, in which case it
    exits).  Calc can be told to exit automatically when any error occurs
    (see option -a and command aborterron).  Comments can be added to a
    line by preceding them with a # .  All input is buffered (unless
    buffering is turned off using the option -b or the command bufferoff)
    so that you can save your work at any point by using the save command.
         The format in Usage2 tells Calc to evaluate the
    commands/expressions on the command line instead of reading a file or
    the keyboard for commands/expressions.  The commands/expressions used
    in this mode are not buffered, so they cannot be saved.
         Using Usage3 puts Calc in column mode.  In this mode it will


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    evaluate the given expression once for each value stored in the
    specified files.  var tells Calc what variable name to assign to the
    values in file1.  var must be a single alphabetic character.  The next
    alphabetic letter is assigned to the contents of file2, etc.  If no
    files are specified, values are read from the keyboard (stdin) and
    assigned to var (you must terminate the input with an end of file which
    is generated by typing CTRL Z on VMS).  Calc reads a value from each of
    the files, sets the corresponding variable, then evaluates the
    expression, and outputs the result.  This process is repeated until
    Calc finds the end of one of the input files.  Each value in the files
    must be separated from the others by whitespace (spaces, tabs, or
    carriage returns).

    MATHEMATICAL EXPRESSIONS

         Expressions conform to normal mathematical notation (note: you
    must use a * for multiplication, you cannot simply use parenthesis).
    They may be of any length, and case is ignored.  All spaces and tabs
    are ignored.  You can also store the results of a calculation by typing
    var=expression where var is any letter from a to z.  For example,
         x = 4*sin(pi/3)/cosh(gamma(5))
    Calc keeps track of the current value of each of the 26 variables, and
    the expressions which were used to define them.  Normally, when a
    variable is defined, the expression is evaluated immediately and the
    result is stored as the current value of the variable.  Calc can be
    told not to evaluate the expression immediately by using the -d or the
    command definitionevaloff.  You may use any of the 26 variables in a
    mathematical expression.  If you use a variable which has not been
    defined, a warning is printed and the value 0 is used.  When a variable
    is used in an expression, Calc checks the definition of the variable
    and automatically updates the current value of the variable if
    necessary.  For example:
         CALC> x=1    # This is a comment.
                            1
         CALC> y=2
                            2
         CALC> r=sqrt(x^2+y^2)
            2.236067977499789
         CALC> 1/r
            0.447213595499958
         CALC> x=2
                            2
         CALC> 1/r
            0.353553390593274
    When a variable's definition includes a reference to itself, it's
    current value is used to compute a new value.  For example:
         CALC> x=1
                            1
         CALC> x=x+.5
                          1.5
         CALC> x
                            2
         CALC> x
                          2.5
    To list the definitions and current values of all variables, use the
    list command.  The following is a list of expressions which are
    supported by the FUNC library, which is responsible for evaluating


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    mathematical expressions in Calc.  Any required explanation of the
    function/operator/constant is given.  'x' and 'y' are used to represent
    any legal expressions (or constants).  All angles are in radians.

    x-y         Binary minus
    -x          Unary minus
    x+y         Binary plus
    x%y         Modulus - gives the remainder that results from
                dividing x by y
    x&y         Logical AND - returns 1 if absolute value of
                both x & y is > EPS (ie. x and y are non-zero).  0 is
                returned otherwise.
    x*y         Product of x and y
    x/y         x divided by y
    x<y         Returns 1 if x < y and 0 if x >= y
    x=y         Returns 1 if the difference between x and y is < EPS
    x>y         Returns 1 if x > y and 0 if x <= y
    x^y         Gives x raised to the power y
    abs(x)      Absolute value
    acos(x)     Inverse cosine of x
    acosh(x)    Inverse hyperbolic cosine
    acot(x)     Inverse cotangent
    acoth(x)    Inverse hyperbolic cotangent
    acsc(x)     Inverse cosecant
    acsch(x)    Inverse hyperbolic cosecant
    asec(x)     Inverse secant
    asin(x)     Inverse sine
    asinh(x)    Inverse hyperbolic sine
    atan(x)     Inverse tangent
    cos(x)      Cosine
    cosh(x)     Hyperbolic cosine
    cot(x)      Cotangent
    coth(x)     Hyperbolic cotangent
    csc(x)      Cosecant
    csch(x)     Hyperbolic cosecant
    eps         Epsilon - a small number
    exp(x)      Exponential:  exp(x) = e^x
    gamma(x)    Gamma function: gamma(x) = integral from t = 0 to infinity
                of t^(x-1)exp(-t)dt.  Note that for positive integers,
                gamma(n+1) = n factorial, also denoted n!.  Due to the fact
                that gamma(x) is computed by different methods for
                different values of x, gamma(x) may be discontinuous in
                places.
    lg(x)       Base 2 logarithm
    ln(x)       Natural logarithm (base e)
    log(x)      Base 10 logarithm
    pi          Pi
    sec(x)      Secant
    sech(x)     Hyperbolic secant
    sin(x)      Sine
    sinh(x)     Hyperbolic sine
    sqr(x)      x squared (x*x)
    sqrt(x)     Square root
    tan(x)      Tangent
    tanh(x)     Hyperbolic tangent
    x|y         Logical OR.  Gives 1 if the absolute value of either
                x or y is > eps.  Gives 0 otherwise.


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    Note that there is some ambiguity about an expression such as x=2.  Is
    this a definition, or an application of the equality operator?  If Calc
    finds a variable as the first character on a line, and an = following
    it, it assumes that it is a definition.  Thus, to force it to view the
    = as an equality operator instead of a definition, you could use (x=2).

    COMMANDS

    The following commands are recognized by Calc.

    aborterroff
                Tells Calc not to abort when it is capable of recovering
    from an error (this is the default).

    aborterron
                Tells Calc to abort when ANY error occurs.

    bufferoff
                Turns off the buffering of user input.  Previously buffered
    input is not lost.  The save command only saves input which has been
    buffered.

    bufferon
                Turns the buffering of user input on (this is the default).
    The save command only saves input which has been buffered.

    definitionevaloff
                Causes calc not to immediately update a variable when it is
    defined.  This is useful when the definition relies on variables which
    have not been defined yet.

    definitionevalon
                Causes Calc to evaluate variable definitions immediately &
    update the current value of the variable (this is the default).

    errfile
                Prompts for the name of a file in which all error messages
    are deposited.

    exit
                Exits from Calc.

    gaussian
                Defines several of the variables with useful constants in
    the gaussian (centimeter, gram, second) system of units.  Be warned
    that previous definitions of these variables will be destroyed.

    infile
                Prompts for the name of a file which will be used for
    input.

    list
                Lists the current values and definitions of all variables.





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    mks
                Defines several of the variables with useful constants in
    the mks (meter, kilogram, second) system of units.  Be warned that
    previous definitions of these variables will be destroyed.

    outfile
                Prompts for the name of a file in which output is stored.

    promptoff
                Discontinues the displaying of CALC> when waiting for
    commands/expressions from the keyboard (stdin).

    prompton
                Tells Calc to display the prompt CALC> when it is waiting
    for commands/expressions from the keyboard (stdin).  This is the
    default.

    quit
                Same as exit.

    repeatoff
                Tells Calc not to echo the input to the output channel
    (this is the default).

    repeaton
                Tells Calc to echo the input to the output channel.  This
    is useful when the output is being directed to a file so that you can
    see both the expressions and their values.

    save
                Prompts for the name of a file in which the
    commands/expressions which have been entered previously are stored.

    OPTIONS

    -o NAME
                Stores all output in a file called NAME.

    -i NAME
                Uses the contents of the file NAME as input.

    -e NAME
                Stores all error messages in the file NAME.

    -a
                Same as the command aborterron.

    -b
                Same as the command bufferoff.

    -d
                Same as the command definitionevaloff.

    -g
                Same as the command gaussian.




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    -m
                Same as the command mks.

    -p
                Same as the command promptoff.

    -r
                Same as the command repeaton.

    EXAMPLES

    An example of Usage1:
                $ CALC
                CALC> x=5
                                   5
                CALC> y=2
                                   2
                CALC> sin(x)*y^4
                 -15.342788394610217
                CALC> exit

    An example of Usage2:
                $ CALC 1+2/3 4/5 pi
                   1.666666666666667
                                 0.8
                   3.141592653589793

    As an example of Usage3, consider the two files:
    file1:
                1
                2
                3
                4
    file2:
                2
                2.5
                3
                3.5
    Then, envoking calc as follows:
                $ CALC -v x x^y file1 file2
                                   1
                   5.656854249492377
                                  27
                   127.9999999999999















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