.\" Automatically generated by Pod::Man 4.11 (Pod::Simple 3.35) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "Bio::Search::BlastUtils 3pm" .TH Bio::Search::BlastUtils 3pm "2020-10-28" "perl v5.30.3" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" Bio::Search::BlastUtils \- Utility functions for Bio::Search:: BLAST objects .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& # This module is just a collection of subroutines, not an object. .Ve .PP See Bio::Search::Hit::BlastHit. .SH "DESCRIPTION" .IX Header "DESCRIPTION" The BlastUtils.pm module is a collection of subroutines used primarily by Bio::Search::Hit::BlastHit objects for some of the additional functionality, such as \s-1HSP\s0 tiling. Right now, the BlastUtils is just a collection of methods, not an object, and it's tightly coupled to Bio::Search::Hit::BlastHit. A goal for the future is to generalize it to work based on the Bio::Search interfaces, then it can work with any objects that implements them. .SH "AUTHOR" .IX Header "AUTHOR" Steve Chervitz .SS "tile_hsps" .IX Subsection "tile_hsps" .Vb 10 \& Usage : tile_hsps( $sbjct ); \& : This is called automatically by Bio::Search::Hit::BlastHit \& : during object construction or \& : as needed by methods that rely on having tiled data. \& Purpose : Collect statistics about the aligned sequences in a set of HSPs. \& : Calculates the following data across all HSPs: \& : \-\- total alignment length \& : \-\- total identical residues \& : \-\- total conserved residues \& Returns : n/a \& Argument : A Bio::Search::Hit::BlastHit object \& Throws : n/a \& Comments : \& : This method is *strongly* coupled to Bio::Search::Hit::BlastHit \& : (it accesses BlastHit data members directly). \& : TODO: Re\-write this to the Bio::Search::Hit::HitI interface. \& : \& : This method performs more careful summing of data across \& : all HSPs in the Sbjct object. Only HSPs that are in the same strand \& : and frame are tiled. Simply summing the data from all HSPs \& : in the same strand and frame will overestimate the actual \& : length of the alignment if there is overlap between different HSPs \& : (often the case). \& : \& : The strategy is to tile the HSPs and sum over the \& : contigs, collecting data separately from overlapping and \& : non\-overlapping regions of each HSP. To facilitate this, the \& : HSP.pm object now permits extraction of data from sub\-sections \& : of an HSP. \& : \& : Additional useful information is collected from the results \& : of the tiling. It is possible that sub\-sequences in \& : different HSPs will overlap significantly. In this case, it \& : is impossible to create a single unambiguous alignment by \& : concatenating the HSPs. The ambiguity may indicate the \& : presence of multiple, similar domains in one or both of the \& : aligned sequences. This ambiguity is recorded using the \& : ambiguous_aln() method. \& : \& : This method does not attempt to discern biologically \& : significant vs. insignificant overlaps. The allowable amount of \& : overlap can be set with the overlap() method or with the \-OVERLAP \& : parameter used when constructing the Blast & Sbjct objects. \& : \& : For a given hit, both the query and the sbjct sequences are \& : tiled independently. \& : \& : \-\- If only query sequence HSPs overlap, \& : this may suggest multiple domains in the sbjct. \& : \-\- If only sbjct sequence HSPs overlap, \& : this may suggest multiple domains in the query. \& : \-\- If both query & sbjct sequence HSPs overlap, \& : this suggests multiple domains in both. \& : \-\- If neither query & sbjct sequence HSPs overlap, \& : this suggests either no multiple domains in either \& : sequence OR that both sequences have the same \& : distribution of multiple similar domains. \& : \& : This method can deal with the special case of when multiple \& : HSPs exactly overlap. \& : \& : Efficiency concerns: \& : Speed will be an issue for sequences with numerous HSPs. \& : \& Bugs : Currently, tile_hsps() does not properly account for \& : the number of non\-tiled but overlapping HSPs, which becomes a problem \& : as overlap() grows. Large values overlap() may thus lead to \& : incorrect statistics for some hits. For best results, keep overlap() \& : below 5 (DEFAULT IS 2). For more about this, see the "HSP Tiling and \& : Ambiguous Alignments" section in L. .Ve .PP See Also : _adjust_contigs(), Bio::Search::Hit::BlastHit .SS "_adjust_contigs" .IX Subsection "_adjust_contigs" .Vb 10 \& Usage : n/a; called automatically during object construction. \& Purpose : Builds HSP contigs for a given BLAST hit. \& : Utility method called by _tile_hsps() \& Returns : \& Argument : \& Throws : Exceptions propagated from Bio::Search::Hit::BlastHSP::matches() \& : for invalid sub\-sequence ranges. \& Status : Experimental \& Comments : This method does not currently support gapped alignments. \& : Also, it does not keep track of the number of HSPs that \& : overlap within the amount specified by overlap(). \& : This will lead to significant tracking errors for large \& : overlap values. .Ve .PP See Also : tile_hsps(), Bio::Search::Hit::BlastHSP::matches .SS "get_exponent" .IX Subsection "get_exponent" .Vb 10 \& Usage : &get_exponent( number ); \& Purpose : Determines the power of 10 exponent of an integer, float, \& : or scientific notation number. \& Example : &get_exponent("4.0e\-206"); \& : &get_exponent("0.00032"); \& : &get_exponent("10."); \& : &get_exponent("1000.0"); \& : &get_exponent("e+83"); \& Argument : Float, Integer, or scientific notation number \& Returns : Integer representing the exponent part of the number (+ or \-). \& : If argument == 0 (zero), return value is "\-999". \& Comments : Exponents are rounded up (less negative) if the mantissa is >= 5. \& : Exponents are rounded down (more negative) if the mantissa is <= \-5. .Ve .SS "collapse_nums" .IX Subsection "collapse_nums" .Vb 10 \& Usage : @cnums = collapse_nums( @numbers ); \& Purpose : Collapses a list of numbers into a set of ranges of consecutive terms: \& : Useful for condensing long lists of consecutive numbers. \& : EXPANDED: \& : 1 2 3 4 5 6 10 12 13 14 15 17 18 20 21 22 24 26 30 31 32 \& : COLLAPSED: \& : 1\-6 10 12\-15 17 18 20\-22 24 26 30\-32 \& Argument : List of numbers sorted numerically. \& Returns : List of numbers mixed with ranges of numbers (see above). \& Throws : n/a .Ve .PP See Also : \fBBio::Search::Hit::BlastHit::seq_inds()\fR .SS "strip_blast_html" .IX Subsection "strip_blast_html" .Vb 10 \& Usage : $boolean = &strip_blast_html( string_ref ); \& : This method is exported. \& Purpose : Removes HTML formatting from a supplied string. \& : Attempts to restore the Blast report to enable \& : parsing by Bio::SearchIO::blast.pm \& Returns : Boolean: true if string was stripped, false if not. \& Argument : string_ref = reference to a string containing the whole Blast \& : report containing HTML formatting. \& Throws : Croaks if the argument is not a scalar reference. \& Comments : Based on code originally written by Alex Dong Li \& : (ali@genet.sickkids.on.ca). \& : This method does some Blast\-specific stripping \& : (adds back a \*(Aq>\*(Aq character in front of each HSP \& : alignment listing). \& : \& : THIS METHOD IS VERY SENSITIVE TO BLAST FORMATTING CHANGES! \& : \& : Removal of the HTML tags and accurate reconstitution of the \& : non\-HTML\-formatted report is highly dependent on structure of \& : the HTML\-formatted version. For example, it assumes that first \& : line of each alignment section (HSP listing) starts with a \& : anchor tag. This permits the reconstruction of the \& : original report in which these lines begin with a ">". \& : This is required for parsing. \& : \& : If the structure of the Blast report itself is not intended to \& : be a standard, the structure of the HTML\-formatted version \& : is even less so. Therefore, the use of this method to \& : reconstitute parsable Blast reports from HTML\-format versions \& : should be considered a temporary solution. .Ve