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46 lines
1.9 KiB
Plaintext
46 lines
1.9 KiB
Plaintext
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Agrep is a tool for fast text searching allowing errors.
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The three most significant features of agrep that are not supported by
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the grep family are
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1) the ability to search for approximate patterns;
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for example, "agrep -2 homogenos foo" will find homogeneous as well
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as any other word that can be obtained from homogenos with at most
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2 substitutions, insertions, or deletions.
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"agrep -B homogenos foo" will generate a message of the form
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best match has 2 errors, there are 5 matches, output them? (y/n)
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2) agrep is record oriented rather than just line oriented; a record
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is by default a line, but it can be user defined;
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for example, "agrep -d '^From ' 'pizza' mbox"
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outputs all mail messages that contain the keyword "pizza".
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Another example: "agrep -d '$$' pattern foo" will output all
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paragraphs (separated by an empty line) that contain pattern.
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3) multiple patterns with AND (or OR) logic queries.
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For example, "agrep -d '^From ' 'burger,pizza' mbox"
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outputs all mail messages containing at least one of the
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two keywords (, stands for OR).
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"agrep -d '^From ' 'good;pizza' mbox" outputs all mail messages
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containing both keywords.
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Putting these options together one can ask queries like
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agrep -d '$$' -2 '<CACM>;TheAuthor;Curriculum;<198[5-9]>' bib
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which outputs all paragraphs referencing articles in CACM between
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1985 and 1989 by TheAuthor dealing with curriculum.
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Two errors are allowed, but they cannot be in either CACM or the year
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(the <> brackets forbid errors in the pattern between them).
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Two technical papers describing agrep are available as:
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agrep.ps.1 is a technical report from June 1991 describing the
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design and implementation of agrep
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ftp://ftp.cs.arizona.edu/agrep/agrep.ps.1.Z
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agrep.ps.2 is a copy of the paper as appeared in the 1992 Winter
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USENIX conference.
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ftp://ftp.cs.arizona.edu/agrep/agrep.ps.2.Z
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- David O'Brien
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obrien@NUXI.com
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