# RegexpExtract
The **RegexpExtract** function returns the substring that matches a regular expression within a string.
If the regular expression contains a [capture group](https://docs.oracle.com/javase/tutorial/essential/regex/groups.html) (`(...)`) and there are one or more matches for that capture group, Analytics Pro returns the first capture group across all matches. Otherwise, Analytics Pro returns the full regular expression.
### Usage
```
RegexpExtract(string, substring, [position])
```
Function arguments:
* **string** (required): The string to search
* **substring** (required): The substring to extract with.
* **position** (optional): The index of the match to return.
> ### 📘When the regular expression contains a slash, quotation or other special character, use a backslash (\\) to escape the special character. Regexp can vary based on the database. Check the documentation of the database you use to find the correct syntax.
### Examples
**Example 1:**
```
RegexpExtract([Address], "[0-9]+")
```
Extracts the first match of numeric characters in the string. No position is specified so position defaults to 1.
**Example 2:**
```
RegexpExtract([Address], "[0-9]+", 2)
```
Extracts the second match of numeric characters in the string.
**Example 3:**
```
RegexpExtract([Address], "\\s*([a-zA-Z]+)", 2)
```
Extracts the second match of alphabetical characters in the string.
**Example 4:**
```
RegexpExtract([Date], "(\\d{2})", 2)
```
Extracts the second match, day of date, of the 2-digit character group in the date.
