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Select (Galaxy tool version 1.0.1)

Select lines from:

that:

the pattern:

here you can enter text or regular expression (for syntax check lower part of this frame)

TIP: If your data is not TAB delimited, use Text Manipulation->Convert

Syntax

The select tool searches the data for lines containing or not containing a match to the given pattern. Regular Expression is introduced in this tool. A Regular Expression is a pattern describing a certain amount of text.

( ) { } [ ] . * ? + ^ $ are all special characters. \ can be used to "escape" a special character, allowing that special character to be searched for.
\A matches the beginning of a string(but not an internal line).
\d matches a digit, same as [0-9].
\D matches a non-digit.
\s matches a whitespace character.
\S matches anything BUT a whitespace.
\t matches a tab.
\w matches an alphanumeric character.
\W matches anything but an alphanumeric character.
( .. ) groups a particular pattern.
\Z matches the end of a string(but not a internal line).
{ n or n, or n,m } specifies an expected number of repetitions of the preceding pattern.
- {n} The preceding item is matched exactly n times.
- {n,} The preceding item is matched n or more times.
- {n,m} The preceding item is matched at least n times but not more than m times.
[ ... ] creates a character class. Within the brackets, single characters can be placed. A dash (-) may be used to indicate a range such as a-z.
. Matches any single character except a newline.
* The preceding item will be matched zero or more times.
? The preceding item is optional and matched at most once.
+ The preceding item will be matched one or more times.
^ has two meaning: - matches the beginning of a line or string. - indicates negation in a character class. For example, [^...] matches every character except the ones inside brackets.
$ matches the end of a line or string.
| Separates alternate possibilities.

Example

^chr([0-9A-Za-z])+ would match lines that begin with chromosomes, such as lines in a BED format file.
(ACGT){1,5} would match at least 1 "ACGT" and at most 5 "ACGT" consecutively.
([^,][0-9]{1,3})(,[0-9]{3})* would match a large integer that is properly separated with commas such as 23,078,651.
(abc)|(def) would match either "abc" or "def".
^\W+# would match any line that is a comment.