How to handle Numerical result out of range?

Shell Programming and Scripting
1

i have this code:

a=hello999999999999999999999999999999999999999999999999999999999
b=`echo ${a} | tr -d '[:alpha:]'`
if [ ${b} -le 0 ] ; then
    echo "Zero"
fi

but when I execute this I am having this error: Numerical result out of range
Anyone know how to handle this?

Thanks!!

2

You could try something like:

a=hello999999999999999999999999999999999999999999999999999999999
b=`echo ${a} | awk 'gsub(/[a-zA-Z]/,x)'`
if [ "${b}" = "" ] ; then
    echo "Zero"
fi
3

I would use something like this:

a=hello999999999999999999999999999999999999999999999999999999999
awk -v n="$a" 'BEGIN {
  gsub(/[^0-9]/, x, n)
  if (n == 0) print "Zero"
  }'

You could easily extend the code to handle negative and floating point numbers too:

a=hello-99999999999999999999999999999999999999999999999999999999.9
awk -v n="$a" 'BEGIN {
  gsub(/[^0-9.-]/, x, n)
  (n ~ /-/ && n ~! /^-/) && gsub(/-/, x, n)
  if (n <= 0) print "Zero"
  }'

And, of course, special care should be taken to handle strings like these:

hello-9-99
h.ello9
4

hmmm i need to compare the number so I cannot use

 if [ "${b}" = "" ] ; then
5

Something like this?

if [ "${b}" = "" ] ; then
  echo "No numbers"
elif [ "${b}" -le 0 ] ; then
  echo "Less or equal to 0"
elif [ "${b}" -gt 0 ] ; then
  echo "Greater then 0"
fi