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dc - desk calculator

Synopsis

Description

Usage

Examples

Attributes

See Also

Diagnostics

/usr/bin/dc[filename]

/usr/xpg6/bin/dc[filename]

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

bcis a preprocessor fordcthat provides infix notation and a C-like syntax that implements functions.bcalso provides reasonable control structures for programs. Seebc(1).

The following constructions are recognized under both

/usr/bin/dcand/usr/xpg6/bin/dc:

numberThe 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.

sxThe top of the stack is popped and stored into a register namedx, wherexmay be any character. If thesis capitalized,xis treated as a stack and the value is pushed on it.

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

dThe top value on the stack is duplicated.

pThe top value on the stack is printed. The top value remains unchanged.

PInterprets the top of the stack as an ASCII string, removes it, and prints it.

fAll values on the stack are printed.

qExits the program. If executing a string, the recursion level is popped by two.

QExits the program. The top value on the stack is popped and the string execution level is popped by that value.

xTreats the top element of the stack as a character string and executes it as a string ofdccommands.

XReplaces 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=xThe top two elements of the stack are popped and compared. Registerxis evaluated if they obey the stated relation.

vReplaces 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 shell command.

cAll values on the stack are popped.

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

IPushes the input base on the top of the stack.

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

OPushes the output base on the top of the stack.

kThe top of the stack is popped, and that value is used as a non-negative 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.

KPushes the current scale factor on the top of the stack.

zThe stack level is pushed onto the stack.

ZReplaces 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.

YDisplaysdcdebugging information.

; :Used bybc(1) for array operations.

The following construction is recognized under

/usr/bin/dc, using the scale of whatever the result is.

+ - / * % ^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.

The following construction is recognized under

/usr/xpg6/bin/dc. The results of division are forced to be a scale of 20.

+ - / * % ^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.Ensures that the scale set prior to division is the scale of the result.

Example 1Printing the first ten values of n!

This example prints the first ten values of n!:

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

See

attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE Availability SUNWesu

bc(1),attributes(5)

xis unimplementedxis an octal number.

out of spaceThe free list is exhausted (too many digits).

out of stack spaceToo many pushes onto the stack (stack overflow).

empty stackToo many pops from the stack (stack underflow).

nesting depthToo many levels of nested execution.

divide by 0Division by zero.

sqrt of neg numberSquare root of a negative number is not defined (no imaginary numbers).

exp not an integerdconly processes integer exponentiation.

exp too bigThe largest exponent allowed is 999.

input base is too largeThe input base x: 2<= x <= 16.

input base is too smallThe input base x: 2<= x <= 16.

output base is too largeThe output base must be no larger thanBC_BASE_MAX.

invalid scale factorScale factor cannot be less than 1.

scale factor is too largeA scale factor cannot be larger thanBC_SCALE_MAX.

symbol table overflowToo many variables have been specified.

invalid indexIndex cannot be less than 1.

index is too largeAn index cannot be larger thanBC_DIM_MAX.

SunOS 5.11 | dc (1) | 29 Aug 2003 |