The hyphen (-) specifies a range when it appears as part of a character class. Use a hyphen to separate the first and last character of a range, such as [a-z] or [0–9]. For example, the command substitute /[0–9]/#/ -e replaces the next occurrence of any digit from 0 through 9 with the pound or hash sign (#).

To specify multiple digits, you would need to enter a numeric specification for each digit, such as [0–9][0-9][0-9] to find any three digit number. The command find /1[0–9][0–9]\.5/ -e would find numbers such as “123.5” and “154.5” but it would not match the string “1ab.5”.

To match a literal - as part of a character class, include it as the first or last character, for example, find -e /[-0-9]/ would match a digit or negative sign.