**Regular Expressions**

. (dot) Any single character except newline

* zero or more occurances of any character

[...] Any single character specified in the set

[^...] Any single character not specified in the set

^ Anchor - beginning of the line

$ Anchor - end of line

\< Anchor - begining of word

\> Anchor - end of word

\(...\) Grouping - usually used to group conditions

\n Contents of nth grouping

[...] Set Examples

[A-Z] The SET from Capital A to Capital Z

[a-z] The SET from lowercase a to lowercase z

[0-9] The SET from 0 to 9 (All numerals)

[./=+] The SET containing . (dot), / (slash), =, and +

[-A-F] The SET from Capital A to Capital F and the dash (dashes must be specified first)

[0-9 A-Z] The SET containing all capital letters and digits and a space

[A-Z][a-zA-Z] In the first position, the SET from Capital A to Capital Z

**Regular Expression Examples**

/Hello/ Matches if the line contains the value Hello

/^TEST$/ Matches if the line contains TEST by itself

/^[a-zA-Z]/ Matches if the line starts with any letter

^.*SET.*$ Select whole line which start with "SET"

/^[a-z].*/ Matches if the first character of the line is a-z and there is at least one more of any

**character**

**"^.* as "**select

**a**phase from beginning up to as word. Can be used to replace "xxxx as c_q6" as "c_q6"

**following it**

/2134$/ Matches if line ends with 2134

/\(21|35\)/ Matches is the line contains 21 or 35

/[0-9]*/ Matches if there are zero or more numbers in the line

/^[^#]/ Matches if the first character is not a # in the line

\r\n[^\r\nO] Matches the lines start with \r\n in previous line but not start with O

Notes:

1. Regular expressions are case sensitive

2. Regular expressions are to be used where pattern is specified

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