| ## EMBOSS: wordmatch

# Program wordmatch

## Function

Finds all exact matches of a given size between 2 sequences

## Description

Finds all exact matches of a given minimum size between 2 sequences displaying the start points in each sequence and the match length.

This program takes two sequences and finds regions where they are identical. These regions are reported in the output file (and optionally) in GFF (Gene Feature Format) files.

It will not find identical regions smaller than the specified wordsize.

## Usage

Here is a sample session with wordmatch.

    % wordmatch sw:hba_human sw:hbb_human
    Output file [hba_human.wordmatch]:
    Word size [4]:

## Command line arguments

       Mandatory qualifiers:
      [-asequence]         sequence   Sequence USA
      [-bsequence]         sequence   Sequence USA
       -wordsize           integer    Word size
      [-outfile]           align      (no help text) align value

       Optional qualifiers: (none)
       Advanced qualifiers:
       -afeatout           featout    File for output of normal tab delimited GFF
                                      features
       -bfeatout           featout    File for output of normal tab delimited GFF
                                      features

       General qualifiers:
      -help                bool       report command line options. More
                                      information on associated and general
                                      qualifiers can be found with -help -verbose

Mandatory qualifiers | Allowed values | Default
--- | --- | ---
[-asequence] (Parameter 1) | Sequence USA | Readable sequence | Required
[-bsequence] (Parameter 2) | Sequence USA | Readable sequence | Required
-wordsize | Word size | Integer 2 or more | 4
[-outfile] (Parameter 3) | (no help text) align value | Alignment file |
Optional qualifiers | Allowed values | Default
(none)
Advanced qualifiers | Allowed values | Default
-afeatout | File for output of normal tab delimited GFF features | Writeable feature table | unknown.gff
-bfeatout | File for output of normal tab delimited GFF features | Writeable feature table | unknown.gff

## Input file format

Any two sequence USAs of the same type (DNA or protein).

## Output file format

The file produced in the above example is:

    FINALLY length = 3
     HBA_HUMAN  HBB_HUMAN Length
            58          63          5
            14          15          4
           116         121          4

The first line ('FINALLY...') gives the number of regions found.

The next line gives the headers for the subsequent columns of data. This consists for the names of the two sequence and the word 'Length'.

Subsequent lines consist of three columns fo numbers separated by spaces or TAB characters. Each line contains the information on one identical region. The first column is the start position in the first sequence of the identical region. The second number is the start position in the second sequence. the third number is the length of the identical region.

If no regions are found, the output file is blank.

## Data files

None.

## Notes

None.

## References

None.

## Warnings

None.

## Diagnostic Error Messages

None.

## Exit status

0 if successful.

## Known bugs

None.

## See also

Program name | Description
--- | ---
matcher | Finds the best local alignments between two sequences
seqmatchall | Does an all-against-all comparison of a set of sequences
supermatcher | Finds a match of a large sequence against one or more sequences
water | Smith-Waterman local alignment

## Author(s)

This application was written by Ian Longden (il@sanger.ac.uk) Informatics Division, The Sanger Centre, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.

## History

Completed 27th November 1998.

## Target users

This program is intended to be used by everyone and everything, from naive users to embedded scripts.

## Comments