dot (.) is considered a special char in a regex expression. And since you are trying to use it here to represent an actual decimal point, you probably need to escape it; ie
regex(.,’^(\d{0,3})(\.[0-9]{0,1})?$’)
dot (.) is considered a special char in a regex expression. And since you are trying to use it here to represent an actual decimal point, you probably need to escape it; ie
regex(.,’^(\d{0,3})(\.[0-9]{0,1})?$’)