Command line calculator

calc

#!/bin/sh
# Command line calculator

# Display usage if no parameters given
if [ -z "$@" ]; then
  echo " ${0##*/} <input> <*decimals> - command line calculator (-h for examples)"
  exit
fi

# Decimal to be carried out to (uses four unless value is given)
if [ -z "$2" ]; then
  decimals=4; else
  decimals=$2
fi

case $1 in
  -h | --help ) echo " Requires quotes.  Examples:"
                echo ' calc "5*((2^3*2)/1.352)"'
                echo ' calc "p=10; n=9; p*n+10"' ;;
  *  )          echo "scale=$decimals;$1" | bc
esac