| dotmatcher

## Wiki

The master copies of EMBOSS documentation are available at http://emboss.open-bio.org/wiki/Appdocs on the EMBOSS Wiki.

Please help by correcting and extending the Wiki pages.

## Function

Draw a threshold dotplot of two sequences

## Description

dotmatcher generates a dotplot from two input sequences. The dotplot is an intuitive graphical representation of the regions of similarity between two sequences. All positions from the first input sequence are compared with all positions from the second input sequence using a specified substitution matrix. The two sequences are the axes of the rectangular dotplot. Wherever there is "similarity" between a position from each sequence a dot is plotted. The threshold conditions for "similarity" are defined by the user.

## Algorithm

All positions from the first input sequence are compared with all positions from the second input sequence and scored, using the specified substitution matrix. This produces a matrix of scores from which local regions of similarity (corresponding to diagonals in the dotplot) are identified. A window of user-specified length is moved along all possible diagonals. Each position in the window corresponds to a pair-wise score from the scoring matrix. The score for the entire window is the sum of the scores for individual positions within it. If the window score is above the user-defined threshold, then a line is plotted on the dotplot corresponding to the window.

## Usage

Here is a sample session with dotmatcher

    % dotmatcher tsw:hba_human tsw:hbb_human -graph cps
    Draw a threshold dotplot of two sequences

    Created dotmatcher.ps

Go to the input files for this example
Go to the output files for this example

## Command line arguments

    Draw a threshold dotplot of two sequences
    Version: EMBOSS:6.2.0

       Standard (Mandatory) qualifiers (* if not always prompted):
      [-asequence]         sequence   Sequence filename and optional format, or
                                      reference (input USA)
      [-bsequence]         sequence   Sequence filename and optional format, or
                                      reference (input USA)
    *  -graph              graph      [$EMBOSS_GRAPHICS value, or x11] Graph type
                                      (ps, hpgl, hp7470, hp7580, meta, cps, x11,
                                      tek, tekt, none, data, xterm, png, gif)
    *  -xygraph            xygraph    [$EMBOSS_GRAPHICS value, or x11] Graph type
                                      (ps, hpgl, hp7470, hp7580, meta, cps, x11,
                                      tek, tekt, none, data, xterm, png, gif)

       Additional (Optional) qualifiers:
       -matrixfile         matrix     [EBLOSUM62 for protein, EDNAFULL for DNA]
                                      This is the scoring matrix file used when
                                      comparing sequences. By default it is the
                                      file 'EBLOSUM62' (for proteins) or the file
                                      'EDNAFULL' (for nucleic sequences). These
                                      files are found in the 'data' directory of
                                      the EMBOSS installation.
       -windowsize         integer    [10] Window size over which to test
                                      threshhold (Integer 3 or more)
       -threshold          integer    [23] Threshold (Integer 0 or more)

       Advanced (Unprompted) qualifiers:
       -stretch            toggle     [N] Display a non-proportional graph

       Associated qualifiers:

       "-asequence" associated qualifiers
       -sbegin1            integer    Start of the sequence to be used
       -send1              integer    End of the sequence to be used
       -sreverse1          boolean    Reverse (if DNA)
       -sask1              boolean    Ask for begin/end/reverse
       -snucleotide1       boolean    Sequence is nucleotide
       -sprotein1          boolean    Sequence is protein
       -slower1            boolean    Make lower case
       -supper1            boolean    Make upper case
       -sformat1           string     Input sequence format
       -sdbname1           string     Database name
       -sid1               string     Entryname
       -ufo1               string     UFO features
       -fformat1           string     Features format
       -fopenfile1         string     Features file name

       "-bsequence" associated qualifiers
       -sbegin2            integer    Start of the sequence to be used
       -send2              integer    End of the sequence to be used
       -sreverse2          boolean    Reverse (if DNA)
       -sask2              boolean    Ask for begin/end/reverse
       -snucleotide2       boolean    Sequence is nucleotide
       -sprotein2          boolean    Sequence is protein
       -slower2            boolean    Make lower case
       -supper2            boolean    Make upper case
       -sformat2           string     Input sequence format
       -sdbname2           string     Database name
       -sid2               string     Entryname
       -ufo2               string     UFO features
       -fformat2           string     Features format
       -fopenfile2         string     Features file name

       "-graph" associated qualifiers
       -gprompt            boolean    Graph prompting
       -gdesc              string     Graph description
       -gtitle             string     Graph title
       -gsubtitle          string     Graph subtitle
       -gxtitle            string     Graph x axis title
       -gytitle            string     Graph y axis title
       -goutfile           string     Output file for non interactive displays
       -gdirectory         string     Output directory

       "-xygraph" associated qualifiers
       -gprompt            boolean    Graph prompting
       -gdesc              string     Graph description
       -gtitle             string     Graph title
       -gsubtitle          string     Graph subtitle
       -gxtitle            string     Graph x axis title
       -gytitle            string     Graph y axis title
       -goutfile           string     Output file for non interactive displays
       -gdirectory         string     Output directory

       General qualifiers:
       -auto               boolean    Turn off prompts
       -stdout             boolean    Write first file to standard output
       -filter             boolean    Read first file from standard input, write
                                      first file to standard output
       -options            boolean    Prompt for standard and additional values
       -debug              boolean    Write debug output to program.dbg
       -verbose            boolean    Report some/full command line options
       -help               boolean    Report command line options and exit. More
                                      information on associated and general
                                      qualifiers can be found with -help -verbose
       -warning            boolean    Report warnings
       -error              boolean    Report errors
       -fatal              boolean    Report fatal errors
       -die                boolean    Report dying program messages
       -version            boolean    Report version number and exit

Qualifier | Type | Description | Allowed values | Default
--- | --- | --- | --- | ---
Standard (Mandatory) qualifiers
[-asequence] (Parameter 1) | sequence | Sequence filename and optional format, or reference (input USA) | Readable sequence | Required
[-bsequence] (Parameter 2) | sequence | Sequence filename and optional format, or reference (input USA) | Readable sequence | Required
-graph | graph | Graph type | EMBOSS has a list of known devices, including ps, hpgl, hp7470, hp7580, meta, cps, x11, tek, tekt, none, data, xterm, png, gif | EMBOSS_GRAPHICS value, or x11
-xygraph | xygraph | Graph type | EMBOSS has a list of known devices, including ps, hpgl, hp7470, hp7580, meta, cps, x11, tek, tekt, none, data, xterm, png, gif | EMBOSS_GRAPHICS value, or x11
Additional (Optional) qualifiers
-matrixfile | matrix | This is the scoring matrix file used when comparing sequences. By default it is the file 'EBLOSUM62' (for proteins) or the file 'EDNAFULL' (for nucleic sequences). These files are found in the 'data' directory of the EMBOSS installation. | Comparison matrix file in EMBOSS data path | EBLOSUM62 for protein EDNAFULL for DNA
-windowsize | integer | Window size over which to test threshhold | Integer 3 or more | 10
-threshold | integer | Threshold | Integer 0 or more | 23
Advanced (Unprompted) qualifiers
-stretch | toggle | Display a non-proportional graph | Toggle value Yes/No | No
Associated qualifiers
"-asequence" associated sequence qualifiers
-sbegin1 -sbegin_asequence | integer | Start of the sequence to be used | Any integer value | 0
-send1 -send_asequence | integer | End of the sequence to be used | Any integer value | 0
-sreverse1 -sreverse_asequence | boolean | Reverse (if DNA) | Boolean value Yes/No | N
-sask1 -sask_asequence | boolean | Ask for begin/end/reverse | Boolean value Yes/No | N
-snucleotide1 -snucleotide_asequence | boolean | Sequence is nucleotide | Boolean value Yes/No | N
-sprotein1 -sprotein_asequence | boolean | Sequence is protein | Boolean value Yes/No | N
-slower1 -slower_asequence | boolean | Make lower case | Boolean value Yes/No | N
-supper1 -supper_asequence | boolean | Make upper case | Boolean value Yes/No | N
-sformat1 -sformat_asequence | string | Input sequence format | Any string |
-sdbname1 -sdbname_asequence | string | Database name | Any string |
-sid1 -sid_asequence | string | Entryname | Any string |
-ufo1 -ufo_asequence | string | UFO features | Any string |
-fformat1 -fformat_asequence | string | Features format | Any string |
-fopenfile1 -fopenfile_asequence | string | Features file name | Any string |
"-bsequence" associated sequence qualifiers
-sbegin2 -sbegin_bsequence | integer | Start of the sequence to be used | Any integer value | 0
-send2 -send_bsequence | integer | End of the sequence to be used | Any integer value | 0
-sreverse2 -sreverse_bsequence | boolean | Reverse (if DNA) | Boolean value Yes/No | N
-sask2 -sask_bsequence | boolean | Ask for begin/end/reverse | Boolean value Yes/No | N
-snucleotide2 -snucleotide_bsequence | boolean | Sequence is nucleotide | Boolean value Yes/No | N
-sprotein2 -sprotein_bsequence | boolean | Sequence is protein | Boolean value Yes/No | N
-slower2 -slower_bsequence | boolean | Make lower case | Boolean value Yes/No | N
-supper2 -supper_bsequence | boolean | Make upper case | Boolean value Yes/No | N
-sformat2 -sformat_bsequence | string | Input sequence format | Any string |
-sdbname2 -sdbname_bsequence | string | Database name | Any string |
-sid2 -sid_bsequence | string | Entryname | Any string |
-ufo2 -ufo_bsequence | string | UFO features | Any string |
-fformat2 -fformat_bsequence | string | Features format | Any string |
-fopenfile2 -fopenfile_bsequence | string | Features file name | Any string |
"-graph" associated graph qualifiers
-gprompt | boolean | Graph prompting | Boolean value Yes/No | N
-gdesc | string | Graph description | Any string |
-gtitle | string | Graph title | Any string | Dotmatcher: $(asequence.usa) vs $(bsequence.usa)
-gsubtitle | string | Graph subtitle | Any string |
-gxtitle | string | Graph x axis title | Any string | $(asequence.name)
-gytitle | string | Graph y axis title | Any string | $(bsequence.name)
-goutfile | string | Output file for non interactive displays | Any string |
-gdirectory | string | Output directory | Any string |
"-xygraph" associated xygraph qualifiers
-gprompt | boolean | Graph prompting | Boolean value Yes/No | N
-gdesc | string | Graph description | Any string |
-gtitle | string | Graph title | Any string | Dotmatcher: $(asequence.usa) vs $(bsequence.usa)
-gsubtitle | string | Graph subtitle | Any string |
-gxtitle | string | Graph x axis title | Any string | $(asequence.name)
-gytitle | string | Graph y axis title | Any string | $(bsequence.name)
-goutfile | string | Output file for non interactive displays | Any string |
-gdirectory | string | Output directory | Any string |
General qualifiers
-auto | boolean | Turn off prompts | Boolean value Yes/No | N
-stdout | boolean | Write first file to standard output | Boolean value Yes/No | N
-filter | boolean | Read first file from standard input, write first file to standard output | Boolean value Yes/No | N
-options | boolean | Prompt for standard and additional values | Boolean value Yes/No | N
-debug | boolean | Write debug output to program.dbg | Boolean value Yes/No | N
-verbose | boolean | Report some/full command line options | Boolean value Yes/No | Y
-help | boolean | Report command line options and exit. More information on associated and general qualifiers can be found with -help -verbose | Boolean value Yes/No | N
-warning | boolean | Report warnings | Boolean value Yes/No | Y
-error | boolean | Report errors | Boolean value Yes/No | Y
-fatal | boolean | Report fatal errors | Boolean value Yes/No | Y
-die | boolean | Report dying program messages | Boolean value Yes/No | Y
-version | boolean | Report version number and exit | Boolean value Yes/No | N

## Input file format

Any 2 sequence USAs of the same type (DNA or protein).

### Input files for usage example

'tsw:hba_human' is a sequence entry in the example protein database 'tsw'

### Database entry: tsw:hba_human

    ID   HBA_HUMAN               Reviewed;         142 AA.
    AC   P69905; P01922; Q1HDT5; Q3MIF5; Q53F97; Q96KF1; Q9NYR7; Q9UCM0;
    DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
    DT   23-JAN-2007, sequence version 2.
    DT   16-JUN-2009, entry version 73.
    DE   RecName: Full=Hemoglobin subunit alpha;
    DE   AltName: Full=Hemoglobin alpha chain;
    DE   AltName: Full=Alpha-globin;
    GN   Name=HBA1;
    GN   and
    GN   Name=HBA2;
    OS   Homo sapiens (Human).
    OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
    OC   Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini;
    OC   Catarrhini; Hominidae; Homo.
    OX   NCBI_TaxID=9606;
    RN   [1]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA] (HBA1).
    RX   MEDLINE=81088339; PubMed=7448866; DOI=10.1016/0092-8674(80)90347-5;
    RA   Michelson A.M., Orkin S.H.;
    RT   "The 3' untranslated regions of the duplicated human alpha-globin
    RT   genes are unexpectedly divergent.";
    RL   Cell 22:371-377(1980).
    RN   [2]
    RP   NUCLEOTIDE SEQUENCE [MRNA] (HBA2).
    RX   MEDLINE=80137531; PubMed=6244294;
    RA   Wilson J.T., Wilson L.B., Reddy V.B., Cavallesco C., Ghosh P.K.,
    RA   Deriel J.K., Forget B.G., Weissman S.M.;
    RT   "Nucleotide sequence of the coding portion of human alpha globin
    RT   messenger RNA.";
    RL   J. Biol. Chem. 255:2807-2815(1980).
    RN   [3]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA] (HBA2).
    RX   MEDLINE=81175088; PubMed=6452630; DOI=10.1073/pnas.77.12.7054;
    RA   Liebhaber S.A., Goossens M.J., Kan Y.W.;
    RT   "Cloning and complete nucleotide sequence of human 5'-alpha-globin
    RT   gene.";
    RL   Proc. Natl. Acad. Sci. U.S.A. 77:7054-7058(1980).
    RN   [4]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    RX   PubMed=6946451; DOI=10.1073/pnas.78.8.5041;
    RA   Orkin S.H., Goff S.C., Hechtman R.L.;
    RT   "Mutation in an intervening sequence splice junction in man.";
    RL   Proc. Natl. Acad. Sci. U.S.A. 78:5041-5045(1981).
    RN   [5]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], AND VARIANT LYS-32.
    RX   MEDLINE=21303311; PubMed=11410421;
    RA   Zhao Y., Xu X.;
    RT   "Alpha2(CD31 AGG-->AAG, Arg-->Lys) causing non-deletional alpha-
    RT   thalassemia in a Chinese family with HbH disease.";

      [Part of this file has been deleted for brevity]

    FT                                /FTId=VAR_002841.
    FT   VARIANT     132    132       S -> P (in Questembert; highly unstable;
    FT                                causes alpha-thalassemia).
    FT                                /FTId=VAR_002843.
    FT   VARIANT     134    134       S -> R (in Val de Marne; O(2) affinity
    FT                                up).
    FT                                /FTId=VAR_002844.
    FT   VARIANT     136    136       V -> E (in Pavie).
    FT                                /FTId=VAR_002845.
    FT   VARIANT     137    137       L -> M (in Chicago).
    FT                                /FTId=VAR_002846.
    FT   VARIANT     137    137       L -> P (in Bibba; unstable; causes alpha-
    FT                                thalassemia).
    FT                                /FTId=VAR_002847.
    FT   VARIANT     137    137       L -> R (in Toyama).
    FT                                /FTId=VAR_035242.
    FT   VARIANT     139    139       S -> P (in Attleboro; O(2) affinity up).
    FT                                /FTId=VAR_002848.
    FT   VARIANT     140    140       K -> E (in Hanamaki; O(2) affinity up).
    FT                                /FTId=VAR_002849.
    FT   VARIANT     140    140       K -> T (in Tokoname; O(2) affinity up).
    FT                                /FTId=VAR_002850.
    FT   VARIANT     141    141       Y -> H (in Rouen/Ethiopia; O(2) affinity
    FT                                up).
    FT                                /FTId=VAR_002851.
    FT   VARIANT     142    142       R -> C (in Nunobiki; O(2) affinity up).
    FT                                /FTId=VAR_002852.
    FT   VARIANT     142    142       R -> H (in Suresnes; O(2) affinity up).
    FT                                /FTId=VAR_002854.
    FT   VARIANT     142    142       R -> L (in Legnano; O(2) affinity up).
    FT                                /FTId=VAR_002853.
    FT   VARIANT     142    142       R -> P (in Singapore).
    FT                                /FTId=VAR_002855.
    FT   CONFLICT     10     10       N -> H (in Ref. 13; BAD97112).
    FT   HELIX         5     16
    FT   HELIX        17     21
    FT   HELIX        22     36
    FT   HELIX        38     43
    FT   HELIX        54     72
    FT   HELIX        74     76
    FT   HELIX        77     80
    FT   HELIX        82     90
    FT   HELIX        97    113
    FT   TURN        115    117
    FT   HELIX       120    137
    FT   TURN        138    140
    SQ   SEQUENCE   142 AA;  15258 MW;  15E13666573BBBAE CRC64;
         MVLSPADKTN VKAAWGKVGA HAGEYGAEAL ERMFLSFPTT KTYFPHFDLS HGSAQVKGHG
         KKVADALTNA VAHVDDMPNA LSALSDLHAH KLRVDPVNFK LLSHCLLVTL AAHLPAEFTP
         AVHASLDKFL ASVSTVLTSK YR
    //

### Database entry: tsw:hbb_human

    ID   HBB_HUMAN               Reviewed;         147 AA.
    AC   P68871; A4GX73; B2ZUE0; P02023; Q13852; Q14481; Q14510; Q45KT0;
    AC   Q549N7; Q6FI08; Q6R7N2; Q8IZI1; Q9BX96; Q9UCD6; Q9UCP8; Q9UCP9;
    DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
    DT   23-JAN-2007, sequence version 2.
    DT   16-JUN-2009, entry version 76.
    DE   RecName: Full=Hemoglobin subunit beta;
    DE   AltName: Full=Hemoglobin beta chain;
    DE   AltName: Full=Beta-globin;
    DE   Contains:
    DE     RecName: Full=LVV-hemorphin-7;
    GN   Name=HBB;
    OS   Homo sapiens (Human).
    OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
    OC   Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini;
    OC   Catarrhini; Hominidae; Homo.
    OX   NCBI_TaxID=9606;
    RN   [1]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    RX   MEDLINE=77126403; PubMed=1019344;
    RA   Marotta C., Forget B., Cohen-Solal M., Weissman S.M.;
    RT   "Nucleotide sequence analysis of coding and noncoding regions of human
    RT   beta-globin mRNA.";
    RL   Prog. Nucleic Acid Res. Mol. Biol. 19:165-175(1976).
    RN   [2]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    RX   MEDLINE=81064667; PubMed=6254664; DOI=10.1016/0092-8674(80)90428-6;
    RA   Lawn R.M., Efstratiadis A., O'Connell C., Maniatis T.;
    RT   "The nucleotide sequence of the human beta-globin gene.";
    RL   Cell 21:647-651(1980).
    RN   [3]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], AND VARIANT LYS-7.
    RX   PubMed=16175509; DOI=10.1086/491748;
    RA   Wood E.T., Stover D.A., Slatkin M., Nachman M.W., Hammer M.F.;
    RT   "The beta-globin recombinational hotspot reduces the effects of strong
    RT   selection around HbC, a recently arisen mutation providing resistance
    RT   to malaria.";
    RL   Am. J. Hum. Genet. 77:637-642(2005).
    RN   [4]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
    RA   Lu L., Hu Z.H., Du C.S., Fu Y.S.;
    RT   "DNA sequence of the human beta-globin gene isolated from a healthy
    RT   Chinese.";
    RL   Submitted (JUN-1997) to the EMBL/GenBank/DDBJ databases.
    RN   [5]
    RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA], AND VARIANT ARG-113.
    RA   Cabeda J.M., Correia C., Estevinho A., Cardoso C., Amorim M.L.,
    RA   Cleto E., Vale L., Coimbra E., Pinho L., Justica B.;
    RT   "Unexpected patterns of globin mutations in thalassemia patients from
    RT   north of Portugal.";

      [Part of this file has been deleted for brevity]

    FT   VARIANT     141    141       A -> V (in Puttelange; polycythemia; O(2)
    FT                                affinity up).
    FT                                /FTId=VAR_003082.
    FT   VARIANT     142    142       L -> R (in Olmsted; unstable).
    FT                                /FTId=VAR_003083.
    FT   VARIANT     143    143       A -> D (in Ohio; O(2) affinity up).
    FT                                /FTId=VAR_003084.
    FT   VARIANT     144    144       H -> D (in Rancho Mirage).
    FT                                /FTId=VAR_003085.
    FT   VARIANT     144    144       H -> P (in Syracuse; O(2) affinity up).
    FT                                /FTId=VAR_003087.
    FT   VARIANT     144    144       H -> Q (in Little Rock; O(2) affinity
    FT                                up).
    FT                                /FTId=VAR_003086.
    FT   VARIANT     144    144       H -> R (in Abruzzo; O(2) affinity up).
    FT                                /FTId=VAR_003088.
    FT   VARIANT     145    145       K -> E (in Mito; O(2) affinity up).
    FT                                /FTId=VAR_003089.
    FT   VARIANT     146    146       Y -> C (in Rainier; O(2) affinity up).
    FT                                /FTId=VAR_003090.
    FT   VARIANT     146    146       Y -> H (in Bethesda; O(2) affinity up).
    FT                                /FTId=VAR_003091.
    FT   VARIANT     147    147       H -> D (in Hiroshima; O(2) affinity up).
    FT                                /FTId=VAR_003092.
    FT   VARIANT     147    147       H -> L (in Cowtown; O(2) affinity up).
    FT                                /FTId=VAR_003093.
    FT   VARIANT     147    147       H -> P (in York; O(2) affinity up).
    FT                                /FTId=VAR_003094.
    FT   VARIANT     147    147       H -> Q (in Kodaira; O(2) affinity up).
    FT                                /FTId=VAR_003095.
    FT   CONFLICT     26     26       Missing (in Ref. 15; ACD39349).
    FT   CONFLICT     42     42       F -> L (in Ref. 13; AAR96398).
    FT   HELIX         6     16
    FT   TURN         21     23
    FT   HELIX        24     35
    FT   HELIX        37     42
    FT   HELIX        44     46
    FT   HELIX        52     57
    FT   HELIX        59     77
    FT   TURN         78     80
    FT   HELIX        82     94
    FT   TURN         95     97
    FT   HELIX       102    119
    FT   HELIX       120    122
    FT   HELIX       125    142
    FT   HELIX       144    146
    SQ   SEQUENCE   147 AA;  15998 MW;  A31F6D621C6556A1 CRC64;
         MVHLTPEEKS AVTALWGKVN VDEVGGEALG RLLVVYPWTQ RFFESFGDLS TPDAVMGNPK
         VKAHGKKVLG AFSDGLAHLD NLKGTFATLS ELHCDKLHVD PENFRLLGNV LVCVLAHHFG
         KEFTPPVQAA YQKVVAGVAN ALAHKYH
    //

## Output file format

An image is output to the requested graphics device.

### Output files for usage example

### Graphics File: dotmatcher.ps

## Data files

It uses the specified matrix substitution file to compare the two sequences.

For protein sequences EBLOSUM62 is used for the substitution matrix. For nucleotide sequence, EDNAFULL is used. Others can be specified.

EMBOSS data files are distributed with the application and stored in the standard EMBOSS data directory, which is defined by the EMBOSS environment variable EMBOSS_DATA.

To see the available EMBOSS data files, run:

    % embossdata -showall

To fetch one of the data files (for example 'Exxx.dat') into your current directory for you to inspect or modify, run:

    % embossdata -fetch -file Exxx.dat

Users can provide their own data files in their own directories. Project specific files can be put in the current directory, or for tidier directory listings in a subdirectory called ".embossdata". Files for all EMBOSS runs can be put in the user's home directory, or again in a subdirectory called ".embossdata".

The directories are searched in the following order:

- . (your current directory)
- .embossdata (under your current directory)
- ~/ (your home directory)
- ~/.embossdata

## Notes

Where the two sequences have substantial regions of similarity, the dots line up to form diagonal lines. It is possible to see at a glance such local regions of similarity. It is also easy to see other features such as repeats (which form parallel diagonal lines), and insertions or deletions (which form breaks or discontinuities in the diagonal lines).

## References

None.

## Warnings

None.

## Diagnostic Error Messages

None.

## Exit status

It always exits with status 0.

## Known bugs

None.

## See also

Program name | Description
--- | ---
dotpath | Draw a non-overlapping wordmatch dotplot of two sequences
dottup | Displays a wordmatch dotplot of two sequences
polydot | Draw dotplots for all-against-all comparison of a sequence set

dottup, by comparison, has no threshold, using a wordmatch-style method. dottup is less sensitive, but substantially faster than dotmatcher.

## Author(s)

Ian Longden (il © sanger.ac.uk)
Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.

## History

Completed 1st June 1999.

## Target users

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

## Comments

None