Remove a character from string

Question

I'm simply trying to remove a % sign from a variable, so I may perform mathmatic calculations on the result. I've tried several things, but none of them seem to work:

$ output="23%"
# usep=$(echo $output | awk '{print $1}' | cut -d '%' -f 1)
# usep=`echo $output | sed 's/\%//g`
# usep=`echo $output | head -c 2`

The variable usep still contains the % character. Any ideas?

Answer 1

You may use POSIX parameter substitution:

$ output="23%"
$ usep=${output%%\%}
$ echo $usep
23