calc - a command line calculator.

SYNOPSYS

calc 'expression'

DESCRIPTION

calc is a command line calculator. It evaluates its arguments as a single awk language expression and prints the result on the standard output.

The results of the last few expressions evaluated by calc are kept in a file by default named ~/.calc. The file is used as a stack. The top value may be accessed in a calc expression as "". Other values on the stack may be accessed with an index on "". for example "[2] is the second value on the stack. The name of the stack file may be set with the -s <filename> option.

In csh it is convenient to alias calc to "=" to mimic the behavior of the IRAF cl compute mode. In addition file name substitution can be turned off within the alias so that "*" need not be escaped within an expression.

  alias = 'set noglob; calc \!*; unset noglob'

OPTIONS

-s <filename>
set the calc stack file name (default ~/.calc).
-D
Print out the awk program to be executed before forking.

EXAMPLES

	john@panic : calc 4 + 6
	10

	john@panic : calc 4:00:00 + 0:30:00
	 4:30:00

	john@panic : calc @ + 2:00:00
	 6:30:00

DETAILS

calc is implemented by wrapping the user expression in a simple awk language program and calling an awk interpreter. The text of the program is:
	BEGIN {	print < expression > }

ENVIRONMENT

TABLEAWK
the name of the awk interpreter to execute. The default interpreter is tawk.
TABLEFUNCTIONS
a path specifying directories to find the source for undefined functions.

SEE ALSO

mawk
an implementation of the awk programming language by Mike Brennan.
tawk
awk language extensions implemented at SAO.
slalink
a tawk extension for inclusion of the slalib astrometry libraries.