Mercurial > repos > bgruening > text_processing
diff sed.xml @ 0:ec66f9d90ef0 draft
initial uploaded
author | bgruening |
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date | Thu, 05 Sep 2013 04:58:21 -0400 |
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children | a4ad586d1403 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/sed.xml Thu Sep 05 04:58:21 2013 -0400 @@ -0,0 +1,110 @@ +<tool id="unixtools_sed_tool" name="Text transformation" version="0.1.1"> + <description>with sed</description> + <requirements> + <requirement type="package" version="4.2.2-sandbox">gnu_sed</requirement> + </requirements> + <command> + sed --sandbox -r $silent -f '$sed_script' '$input' > '$output' + </command> + <inputs> + <param format="txt" name="input" type="data" label="File to process" /> + + <param name="url_paste" type="text" area="true" size="5x35" label="SED Program" help=""> + <sanitizer> + <valid initial="string.printable"> + <remove value="'"/> + </valid> + </sanitizer> + </param> + + <param name="silent" type="select" label="operation mode" help="(Same as 'sed -n', leave at 'normal' unless you know what you're doing)" > + <option value="">normal</option> + <option value="-n">silent</option> + </param> + + </inputs> + <configfiles> + <configfile name="sed_script"> + $url_paste + </configfile> + </configfiles> + <tests> + <test> + <param name="input" value="unix_sed_input1.txt" /> + <output name="output" file="unix_sed_output1.txt" /> + <param name="url_paste" value="1d ; s/foo/bar/" /> + <param name="silent" value="" /> + </test> + <test> + <param name="input" value="unix_sed_input1.txt" /> + <output name="output" file="unix_sed_output2.txt" /> + <param name="url_paste" value="/foo/ { s/foo/baz/g ; p }" /> + <param name="silent" value="silent" /> + </test> + </tests> + <outputs> + <data format="input" name="output" metadata_source="input" /> + </outputs> +<help> + +**What it does** + +This tool runs the unix **sed** command on the selected data file. + +.. class:: infomark + +**TIP:** This tool uses the **extended regular** expression syntax (same as running 'sed -r'). + + + +**Further reading** + +- Short sed tutorial (http://www.linuxhowtos.org/System/sed_tutorial.htm) +- Long sed tutorial (http://www.grymoire.com/Unix/Sed.html) +- sed faq with good examples (http://sed.sourceforge.net/sedfaq.html) +- sed cheat-sheet (http://www.catonmat.net/download/sed.stream.editor.cheat.sheet.pdf) +- Collection of useful sed one-liners (http://student.northpark.edu/pemente/sed/sed1line.txt) + +----- + +**Sed commands** + +The most useful sed command is **s** (substitute). + +**Examples** + +- **s/hsa//** will remove the first instance of 'hsa' in every line. +- **s/hsa//g** will remove all instances (beacuse of the **g**) of 'hsa' in every line. +- **s/A{4,}/--&--/g** will find sequences of 4 or more consecutive A's, and once found, will surround them with two dashes from each side. The **&** marker is a place holder for 'whatever matched the regular expression'. +- **s/hsa-mir-([^ ]+)/short name: \\1 full name: &/** will find strings such as 'hsa-mir-43a' (the regular expression is 'hsa-mir-' followed by non-space characters) and will replace it will string such as 'short name: 43a full name: hsa-mir-43a'. The **\\1** marker is a place holder for 'whatever matched the first parenthesis' (similar to perl's **$1**) . + + +**sed's Regular Expression Syntax** + +The select 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. + + +**Note**: SED uses extended regular expression syntax, not Perl syntax. **\\d**, **\\w**, **\\s** etc. are **not** supported. + +</help> +</tool>