DC(C)                    XENIX System V                     DC(C)



     Name
          dc - Invokes an arbitrary precision calculator.

     Syntax
          dc [ file ]

     Description
          dc is an arbitrary precision arithmetic package.  Ordinarily
          it operates on decimal integers, but you may specify an
          input base, output base, and a number of fractional digits
          to be maintained.  The overall structure of dc is a stacking
          (reverse Polish) calculator.  If an argument is given, input
          is taken from that file until its end, then from the
          standard input.  The following constructions are recognized:

          number
                The value of the number is pushed on the stack.  A
                number is an unbroken string of the digits 0-9.  It
                may be preceded by an underscore (_) to input a
                negative number.  Numbers may contain decimal points.

          + - / * % ^
                The top two values on the stack are added (+),
                subtracted (-), multiplied (*), divided (/),
                remaindered (%), or exponentiated (^).  The two
                entries are popped off the stack; the result is pushed
                on the stack in their place.  Any fractional part of
                an exponent is ignored.

          sx    The top of the stack is popped and stored into a
                register named x, where x may be any character.  If
                the s is capitalized, x is treated as a stack and the
                value is pushed on it.

          lx    The value in register x is pushed on the stack.  The
                register x is not altered.  All registers start with
                zero value.  If the l is capitalized, register x is
                treated as a stack and its top value is popped onto
                the main stack.

          d     The top value on the stack is duplicated.

          p     The top value on the stack is printed.  The top value
                remains unchanged.  p interprets the top of the stack
                as an ASCII string, removes it, and prints it.

          f     All values on the stack are printed.

          q     Exits the program.  If executing a string, the
                recursion level is popped by two.  If q is
                capitalized, the top value on the stack is popped and
                the string execution level is popped by that value.



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          x     Treats the top element of the stack as a character
                string and executes it as a string of dc commands.

          X     Replaces the number on the top of the stack with its
                scale factor.

          [ ... ]
                Puts the bracketed ASCII string onto the top of the
                stack.

          <x   >x   =x
                The top two elements of the stack are popped and
                compared.  Register x is evaluated if they obey the
                stated relation.

          v     Replaces the top element on the stack by its square
                root.  Any existing fractional part of the argument is
                taken into account, but otherwise the scale factor is
                ignored.

          !     Interprets the rest of the line as a XENIX command.

          c     All values on the stack are popped.

          i     The top value on the stack is popped and used as the
                number radix for further input.

          I     Pushes the input base on the top of the stack.

          o     The top value on the stack is popped and used as the
                number radix for further output.

          O     Pushes the output base on the top of the stack.

          k     The top of the stack is popped, and that value is used
                as a nonnegative scale factor; the appropriate number
                of places are printed on output, and maintained during
                multiplication, division, and exponentiation.  The
                interaction of scale factor, input base, and output
                base will be reasonable if all are changed together.

          z     The stack level is pushed onto the stack.

          Z     Replaces the number on the top of the stack with its
                length.

          ?     A line of input is taken from the input source
                (usually the terminal) and executed.

          ; :   Used by bc for array operations.

     Example



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     DC(C)                    XENIX System V                     DC(C)



          This example prints the first ten values of n!:

             [la1+dsa*pla10>y]sy
             0sa1
             lyx

     See Also
          bc(C)

     Diagnostics
          x is unimplemented       The octal number x corresponds to a
                                   character that is not implemented
                                   as a command

          stack empty              Not enough elements on the stack to
                                   do what was asked

          Out of space             The free list is exhausted (too
                                   many digits)

          Out of headers           Too many numbers being kept around

          Out of pushdown          Too many items on the stack

          Nesting Depth            Too many levels of nested execution

     Notes
          bc is a preprocessor for dc, providing infix notation and a
          C-like syntax which implements functions and reasonable
          control structures for programs.  For interactive use, bc is
          preferred to dc .
























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