Regular expressions

Regular expressions provide a way to search for a general pattern of text rather than a specific piece of text. For example, you can use a regular expression to search for license plates that are based on a partial sighting.

A regular expression is written as a sequence of characters. The syntax combines the text for which you are searching with special characters to define the pattern.

Note:
Unlike a simple search, a regular expression search is case-sensitive.
Table 1. Supported regular expression characters
Character Description
. Matches a single character. For example, ABC 123. matches ABC 1234 and ABC 1235.
Note:
This character is equivalent to the '?' character when you are searching for files by name in Windows Explorer.
^ Matches the start of a line. For example, ^ABC matches ABC 1234 and ABC 2345 but not 1234 ABC.
$ Matches the end of a line. For example, 1234$ matches ABC 1234 and CBA 1234 but not 1234 ABC.
* Matches zero, one or more repeats of the previous character. For example xx* matches xx, xxxxxxx
[] Matches any character inside the brackets. You can specify a range of characters, for example [0-9], [a-z].
[^] Matches any characters except the characters in the list. For example: [^ABC] matches any character other than "A", "B", or "C".
| Matches either the expression before the bar OR the expression after the bar. For example 1234$|1235$ matches any license plates that end in 1234 or 1235.
\ Ignores the special meaning of the next character. For example, abc$|def$|\|$matches any text that ends in abc, def or |.

Analyst's Notebook does not support extended regular expression combinations (), \(\), \>, \<, \{, \}, and \digit.