#

| Chapter 2 UNIX Commands |

## dc

    dc [file]

An interactive desk calculator program that performs arbitrary- precision integer arithmetic (input may be taken from a `file`). Normally you don't run dc directly, since it's invoked by bc (see bc). dc provides a variety of one-character commands and operators that perform arithmetic; dc works like a Reverse Polish calculator; therefore, operators and commands follow the numbers they affect. Operators include + - / `* %` ^ (as in C); some simple commands include:

p

  Print current result.

q

  Quit dc.

c

  Clear all values on the stack.

v

  Take square root.

i

  Change input base; similar to bc's ibase.

o

  Change output base; similar to bc's obase.

k

  Set scale factor (number of digits after decimal); similar to bc's scale.

!

  Remainder of line is a UNIX command.

### Examples

>     3 2 ^ p	Evaluate 3 squared, then print result.
>     9
>     8 * p	Current value (9) times 8, then print result.
>     72
>     47 - p	Subtract 47 from 72, then print result.
>     25
>     v p	Square root of 25, then print result.
>     5
>     2 o p	Display current result in base 2.
>     101

Note: Spaces are not needed except between numbers.

Reference: dbx |  | Reference: dd