awk help with string spliting

Hello all, I am having a problem with awk's string split function.

I have a string that has a number at the end, I am trying to remove the alpha portion of the string and just have the numeric part. Here is my code and the result:

BEGIN {
word = "$category121";

split(word, a, 121)
print a[1]}

robert@RF5:~$ awk -f switch2.awk
$category
robert@RF5:~$
-------------------------

Is there a way to split "$category" and "121" in to two seperate variables?

Thank you for your help.
Robert

Another approach using shell and "tr", if thats ok:

$> word='$category121'
$> PART1=`echo $word| tr -d '[:digit:]'`
$> echo $PART1
$category
$> PART2=`echo $word| tr -d '[:alpha:]$'`
$> echo $PART2
121

Zaxxon:

Thank you! I will give that a try.

~Robert