bc(1)                               CLIX                               bc(1)



  NAME

    bc - Processes arbitrary-precision arithmetic language

  SYNOPSIS

    b [-c] [-l] [file ... ]

  FLAGS

    -c   Compiles only.  The output is send to stdout.

    -l   Indicates that the argument stands for the name of an arbitrary
         precision math library.

  DESCRIPTION

    The bc utility is an interactive processor for a language that resembles C
    but provides unlimited precision arithmetic.  It takes input from any
    files given, then reads stdin.  The bc utility is actually a preprocessor
    for dc, which it invokes automatically unless the -c flag is present.  In
    this case the dc input is sent to stdout instead.

    The syntax for bc commands is as follows; L is one of the letters a-z, E
    is an expression, S is an statement.

    Comments

    ⊕  enclosed in /* and */.

    Names are:

    ⊕  simple variables: L

    ⊕  array elements: L[E]

    ⊕  One of the words ibase, obase, and scale

    Other operands:

    ⊕  Arbitrarily long numbers with optional sign and decimal point.

    ⊕  (E)

    ⊕  sqrt(E)

    ⊕  length(E)    (number of significant decimal digits)

    ⊕  scale(E)    (number of digits right of decimal point)

    ⊕  L (E, ... , E)



  2/94 - Intergraph Corporation                                              1

  bc(1)                               CLIX                               bc(1)



    Operators:

    ⊕  +   -   *   /   %   ^    (% is remainder; ^ is power)

    ⊕  ++   --    (prefix and postfix; apply to names)

    ⊕  ==   <=   >=   !=   <   >

    ⊕  =   =+   =-   =*   =/

    ⊕  =%   =^

    Statements:

    ⊕  E

    ⊕  {S; ... ; S}

    ⊕  if (E) S

    ⊕  while (E) S

    ⊕  for (E; E; E) S

    ⊕  null statement

    ⊕  break

    ⊕  quit

    Function definitions:

    ⊕  define L (L, ... , L) {
            auto L, ... , L
            S; ... ; S
            return(E)
            }

    Functions in the -l math library

    ⊕  s(x) sine

    ⊕  c(x) cosine

    ⊕  e(x) exponential

    ⊕  l(x) log

    ⊕  a(x) arctangent

    ⊕  j(n,x)    Bessel function



  2                                              Intergraph Corporation - 2/94

  bc(1)                               CLIX                               bc(1)



    All function arguments are passed by value.

    The value of a statement that is an expression is displayed unless the
    main operator is an assignment.  Either semicolons or newlines may
    separate statements.  Assignment to scale influences the number of digits
    to be retained on arithmetic operations in the manner of dc.  Assignments
    to ibase or obase set the input and output number radix respectively.

    The same letter may be used as an array, a function, and a simple variable
    simultaneously.  All variables are global to the command.  ``Auto''
    variables are pushed down during function calls.  When using arrays as
    function arguments or defining them as automatic variables, empty square
    brackets must follow the array name.

  EXAMPLES

    1.  To define a function to compute an approximate value of the
        exponential function:

        scale = 20
        define e(x){
             auto a, b, c, i, s
             a = 1
             b = 1
             s = 1
             for(i=1; 1==1; i++){
                  a = a*x
                  b = b*i
                  c = a/b
                  if(c == 0) return(s)
                  s = s+c
             }
        }


    2.  To display approximate values of the exponential function of the first
        ten integers:

        for(i=1; i<=10; i++) e(i)


  FILES

    /usr/lib/lib.b   Mathematical library

    /usr/bin/dc      Desk calculator proper

  NOTES

    The bc command does not yet recognize the logical operators, && and ||.




  2/94 - Intergraph Corporation                                              3

  bc(1)                               CLIX                               bc(1)



    A for statement must have all three expressions (E's).

    A quit statement is interpreted when read, not when executed.

  EXIT VALUES

    Exit values are not valid.

  RELATED INFORMATION

    Commands: dc(1)











































  4                                              Intergraph Corporation - 2/94