REGEXPREP Regular Expression Replacement Function

Section: String Functions

Usage

Replaces regular expressions in the provided string. The syntax for its use is 
  outstring = regexprep(instring,pattern,replacement,modes)

Here instring is the string to be operated on. And pattern is a regular expression of the type accepted by regexp. For each match, the contents of the matched string are replaced with the replacement text. Tokens in the regular expression can be used in the replacement text using $N where N is the number of the token to use. You can also specify the same mode flags that are used by regexp.