view tools/unix_tools/find_and_replace.xml @ 1:cdcb0ce84a1b

author xuebing
date Fri, 09 Mar 2012 19:45:15 -0500
parents 9071e359b9a3
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<tool id="cshl_find_and_replace" name="Find and Replace">
  <command interpreter="perl">
	#if $searchwhere.choice == "column":
		-c $searchwhere.column
	#end if
	-o $output 
    <param format="txt" name="input" type="data" label="File to process" />

    <!-- Note: the parameter ane MUST BE 'url_paste' -
         This is a hack in the galaxy library (see ./lib/galaxy/util/ line 142)
	 If the name is 'url_paste' the string won't be sanitized, and all the non-alphanumeric characters 
	 will be passed to the shell script -->
	 <param name="url_paste" type="text" size="20" label="Find pattern" help="Use simple text, or a valid regular expression (without backslashes // ) " > 
    		<validator type="expression" message="Invalid Program!">value.find('\'')==-1</validator>

	 <param name="file_data" type="text" size="20" label="Replace with" help="Use simple text, or &amp; (ampersand) and \\1 \\2 \\3 to refer to matched text. See examples below." >
    		<validator type="expression" message="Invalid Program!">value.find('\'')==-1</validator>

	<param name="is_regex" type="boolean" checked="false" truevalue="-r" falsevalue="" label="Find-Pattern is a regular expression" 
		help="see help section for details." />

	<param name="caseinsensitive" type="boolean" checked="false" truevalue="-i" falsevalue="" label="Case-Insensitive search" 
		help="" />

	<param name="wholewords" type="boolean" checked="false" truevalue="-w" falsevalue="" label="find whole-words" 
		help="ignore partial matches (e.g. 'apple' will not match 'snapple') " />

	<param name="skip_first_line" type="boolean" checked="false" truevalue="-s" falsevalue="" label="Ignore first line" 
		help="Select this option if the first line contains column headers. Text in the line will not be replaced. " />

	<conditional name="searchwhere">
		<param name="choice" type="select" label="Replace text in">
			<option value="line" selected="true">entire line</option>
			<option value="column">specific column</option>

		<when value="line">

		<when value="column">
    			<param name="column" label="in column" type="data_column" data_ref="input" accept_default="true" />

    <data format="input" name="output" metadata_source="input" />


**What it does**

This tool finds &amp; replaces text in an input dataset.

.. class:: infomark

The **pattern to find** can be a simple text string, or a perl **regular expression** string (depending on *pattern is a regex* check-box).

.. class:: infomark

When using regular expressions, the **replace pattern** can contain back-references ( e.g. \\1 )

.. class:: infomark

This tool uses Perl regular expression syntax.


**Examples of *regular-expression* Find Patterns**

- **HELLO**     The word 'HELLO' (case sensitive).
- **AG.T**      The letters A,G followed by any single character, followed by the letter T.
- **A{4,}**     Four or more consecutive A's.
- **chr2[012]\\t**       The words 'chr20' or 'chr21' or 'chr22' followed by a tab character.
- **hsa-mir-([^ ]+)**        The text 'hsa-mir-' followed by one-or-more non-space characters. When using parenthesis, the matched content of the parenthesis can be accessed with **\1** in the **replace** pattern.

**Examples of Replace Patterns**

- **WORLD**  The word 'WORLD' will be placed whereever the find pattern was found.
- **FOO-&amp;-BAR**  Each time the find pattern is found, it will be surrounded with 'FOO-' at the begining and '-BAR' at the end. **&amp;** (ampersand) represents the matched find pattern.
- **\\1**   The text which matched the first parenthesis in the Find Pattern.


**Example 1**

**Find Pattern:** HELLO
**Replace Pattern:** WORLD
**Regular Expression:** no
**Replace what:** entire line

Every time the word HELLO is found, it will be replaced with the word WORLD. 


**Example 2**

**Find Pattern:** ^chr 
**Replace Pattern:** (empty)
**Regular Expression:** yes
**Replace what:** column 11

If column 11 (of every line) begins with ther letters 'chr', they will be removed. Effectively, it'll turn "chr4" into "4" and "chrXHet" into "XHet"


**Perl's Regular Expression Syntax**

The Find &amp; Replace tool searches the data for lines containing or not containing a match to the given pattern. A Regular Expression is a pattern descibing 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.
- **^** matches the beginning of a string(but not an internal line).
- **(** .. **)** groups a particular pattern.
- **{** 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 ismatched 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. 
- **\\d** matches a single digit
- **\\w** matches a single letter or digit or an underscore.
- **\\s** matches a single white-space (space or tabs).