check input = "empty" and "numeric"


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# 1  
check input = "empty" and "numeric"

Hi

how to check input is "empty" and "numeric" in ksh?

e.g:
./myscript.ksh k
output show: invalid number input

./myscript.ksh
output show: no input

./myscript.ksh 10
output show: input is numeric
# 2  
checking for empty is easy

Code:
if test "$VAR" = ""
then 
    echo empty
fi

checking for numeric, I would use case,

Code:
case "$VAR" in
[0-9]* )
         echo at least it starts with a numeric...
        ;;
* )
       ;;
esac

# 3  
thanks. is working fine.
# 4  
If you want to be sure the entire argument is numeric (rather than just the first character), use grep:
Code:
if echo $VAR | grep [^0-9] > /dev/null
then
  echo "Some non-numeric characters detected"
else
  echo "All numeric"
fi

# 5  
The case statement itself can manage full numeric check (for both integers and floating point numbers):

Quote:
#!/usr/bin/ksh

VAR=$1

if test "$VAR" = ""
then
echo empty
fi

case $VAR in
+([0-9])*(.)*([0-9]) )
echo it definitely is numeric
;;
* )
;;
esac
HTH
# 6  
this is the best +([0-9])*(.)*([0-9]) )
Smilie
# 7  
Tests for an empty value can be done using the "-z" option of test:

Code:
if [ -z "$var" ] ; then
....

bakunin
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