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Bio::Tools::Run::StandUsereContributed PerlBio::Tools::Run::StandAloneBlast(3)

       Bio::Tools::Run::StandAloneBlast	- Object for the local execution of
       the NCBI	BLAST program suite (blastall, blastpgp, bl2seq).  There is
       experimental support for	WU-Blast and NCBI rpsblast.

	# Local-blast "factory object" creation	and blast-parameter
	# initialization:
	@params	= (-database =>	'swissprot', -outfile => 'blast1.out');
	$factory = Bio::Tools::Run::StandAloneBlast->new(@params);

	# Blast	a sequence against a database:
	$str = Bio::SeqIO->new(-file=>'t/amino.fa', -format => 'Fasta');
	$input = $str->next_seq();
	$input2	= $str->next_seq();
	$blast_report =	$factory->blastall($input);

	# Run an iterated Blast	(psiblast) of a	sequence against a database:
	$factory->j(3);	   # 'j' is blast parameter for	# of iterations
	$factory = Bio::Tools::Run::StandAloneBlast->new(@params);
	$blast_report =	$factory->blastpgp($input);

	# Use blast to align 2 sequences against each other:
	$factory = Bio::Tools::Run::StandAloneBlast->new(-outfile => 'bl2seq.out');
	$factory->bl2seq($input, $input2);

	# Experimental support for WU-Blast 2.0
	my $factory = Bio::Tools::Run::StandAloneBlast->new(-program =>"wublastp",
							    -database =>"swissprot",
							    -e => 1e-20);
	my $blast_report = $factory->wublast($seq);

	# Experimental support for NCBI	rpsblast
	my $factory = Bio::Tools::Run::StandAloneBlast->new(-db	=> 'CDD/Cog',
							    -expect => 0.001);
	$factory->F('T'); # turn on SEG	filtering of query sequence
	my $blast_report = $factory->rpsblast($seq);

	# Use the experimental fast Blast parser, 'blast_pull'
	my $factory = Bio::Tools::Run::StandAloneBlast->new(-_READMETHOD =>'blast_pull',

	# Various additional options and input formats are available,
	# see the DESCRIPTION section for details.

       This DESCRIPTION	only documents Bio::Tools::Run::StandAloneBlast, a
       Bioperl object for running the NCBI standAlone BLAST package. Blast
       itself is a large & complex program - for more information regarding
       BLAST, please see the BLAST documentation which accompanies the BLAST
       distribution. BLAST is available	from

       A source	of confusion in	documenting a BLAST interface is that the term
       "program" is used in - at least - three different ways in the BLAST
       documentation. In this DESCRIPTION, "program" will refer	to the BLAST
       routine set by the BLAST	"-p" parameter that can	be set to blastn,
       blastp, tblastx etc. We will use	the term Blast "executable" to refer
       to the various different	executable files that may be called - ie.
       blastall, blastpgp or bl2seq. In	addition, there	are several BLAST
       capabilities, which are also referred to	as "programs", and are
       implemented by using specific combinations of BLAST executables,
       programs	and parameters.	They will be referred by their specific	names
       - eg PSIBLAST and PHIBLAST.

       Before running StandAloneBlast it is necessary: to install BLAST	on
       your system, to edit set	the environmental variable $BLASTDIR or	your
       $PATH variable to point to the BLAST directory, and to ensure that
       users have execute privileges for the BLAST program.

       If the databases	which will be searched by BLAST	are located in the
       data subdirectory of the	blast program directory	(the default
       installation location), StandAloneBlast will find them; however,	if the
       database	files are located in any other location, environmental
       variable	$BLASTDATADIR will need	to be set to point to that directory.

       The use of the StandAloneBlast module is	as follows: Initially, a local
       blast "factory object" is created. The constructor may be passed	an
       optional	array of (non-default) parameters to be	used by	the factory,

	@params	= (-program => 'blastn', -database => 'ecoli.nt');
	$factory = Bio::Tools::Run::StandAloneBlast->new(@params);

       Any parameters not explicitly set will remain as	the defaults of	the
       BLAST executable. Note each BLAST executable has	somewhat different
       parameters and options. See the BLAST Documentation for a description
       or run the BLAST	executable from	the command line followed solely with
       a "-" to	see a list of options and default values for that executable;
       eg >blastall -.

       BLAST parameters	can be changed and/or examined at any time after the
       factory has been	created. The program checks that any parameter/switch
       being set/read is valid.	Except where specifically noted,
       StandAloneBlast uses the	same single-letter, case-sensitive parameter
       names as	the actual blast program. Currently no checks are included to
       verify that parameters are of the proper	type (e.g. string or numeric)
       or that their values are	within the proper range.

       As an example, to change	the value of the Blast parameter 'e' ('e' is
       the parameter for expectation-value cutoff)

	 $expectvalue =	0.01;

       Note that for improved script readibility one can modify	the name of
       the (ncbi) BLAST	parameters as desired as long as the initial letter
       (and case) of the parameter are preserved, e.g.:


       Unfortunately, some of the BLAST	parameters are not the single letter
       one might expect	(eg "iteration round" in blastpgp is 'j').  Again one
       can check by using, for example:

	 > blastpgp -

       Wublast parameters need to be complete (ie. don't truncate them to
       their first letter), but	are case-insensitive.

       Once the	factory	has been created and the appropriate parameters	set,
       one can call one	of the supported blast executables. The	input
       sequence(s) to these executables	may be fasta file(s) as	described in
       the BLAST documentation.

	 $inputfilename	= 't/testquery.fa';
	 $blast_report = $factory->blastall($inputfilename);

       In addition, sequence input may be in the form of either	a Bio::Seq
       object or (a reference to) an array of Bio::Seq objects,	e.g.:

	 $input	= Bio::Seq->new(-id => "test query",
	 $blast_report = $factory->blastall($input);

       NOTE: Use of the	BPlite method has been deprecated and is no longer

       For blastall and	non-psiblast blastpgp runs, report object is a
       Bio::SearchIO object, selected by the user with the parameter
       _READMETHOD. The	leading	underscore is needed to	distinguish this
       option from options which are passed to the BLAST executable. The
       default parser is Bio::SearchIO::blast. In any case, the	"raw" blast
       report is also available. The filename is set by	the 'outfile'
       parameter and has the default value of "blastreport.out".

       For psiblast execution in the BLAST "jumpstart" mode, the program must
       be passed (in addition to the query sequence itself) an alignment
       containing the query sequence (in the form of a SimpleAlign object) as
       well as a "mask"	specifying at what residues position-specific scoring
       matrices	(PSSMs)	are to used and	at what	residues default scoring
       matrices	(eg BLOSUM) are	to be used. See	psiblast documentation for
       more details. The mask itself is	a string of 0's	and 1's	which is the
       same length as each sequence in the alignment and has a "1" at
       locations where (PSSMs) are to be used and a "0"	at all other
       locations. So for example:

	 $str =	Bio::AlignIO->new(-file	=> "cysprot.msf",
				  -format => 'msf');
	 $aln =	$str->next_aln();
	 $len =	$aln->length_aln();
	 $mask = '1' x $len;
	 # simple case where PSSM's to be used at all residues
	 $report = $factory->blastpgp("cysprot1.fa", $aln, $mask);

       For bl2seq execution,	can be combined	with to directly produce a	SimpleAlign object from	the alignment
       of the two sequences produced by	bl2seq as in:

	 # Get 2 sequences
	 $str =	Bio::SeqIO->new(-file=>'t/amino.fa' , -format => 'Fasta');
	 my $seq3 = $str->next_seq();
	 my $seq4 = $str->next_seq();

	 # Run bl2seq on them
	 $factory = Bio::Tools::Run::StandAloneBlast->new(-program => 'blastp',
							  -outfile => 'bl2seq.out');
	 my $bl2seq_report = $factory->bl2seq($seq3, $seq4);

	 # Use to create a SimpleAlign object from the bl2seq report
	 $str =	Bio::AlignIO->new(-file=> 'bl2seq.out',-format => 'bl2seq');
	 $aln =	$str->next_aln();

       For more	examples of syntax and use of, the user is
       encouraged to run the scripts	in the bioperl
       examples/tools directory	and StandAloneBlast.t in the bioperl t/

   Mailing Lists
       User feedback is	an integral part of the	evolution of this and other
       Bioperl modules.	Send your comments and suggestions preferably to one
       of the Bioperl mailing lists.  Your participation is much appreciated.			- General discussion	- About	the mailing lists

       Please direct usage questions or	support	issues to the mailing list:

       rather than to the module maintainer directly. Many experienced and
       reponsive experts will be able look at the problem and quickly address
       it. Please include a thorough description of the	problem	with code and
       data examples if	at all possible.

   Reporting Bugs
       Report bugs to the Bioperl bug tracking system to help us keep track
       the bugs	and their resolution.  Bug reports can be submitted via	the

AUTHOR - Peter Schattner
       Email schattner at

MAINTAINER - Torsten Seemann
       Email torsten at

       Sendu Bala (reimplementation)

       The rest	of the documentation details each of the object	methods.
       Internal	methods	are usually preceded with a _

	Title	: new
	Usage	: my $obj = Bio::Tools::Run::StandAloneBlast->new();
	Function: Builds a newBio::Tools::Run::StandAloneBlast object
	Returns	: Bio::Tools::Run::StandAloneNCBIBlast or StandAloneWUBlast
	Args	: -quiet => boolean # make program execution quiet
		  -_READMETHOD => 'BLAST' (default, synonym 'SearchIO')	|| 'blast_pull'
				  # the	parsing	method,	case insensitive

       Essentially all BLAST parameters	can be set via
       Some of the most	commonly used parameters are listed below. All
       parameters have defaults	and are	optional except	for -p in those
       programs	that have it. For a complete listing of	settable parameters,
       run the relevant	executable BLAST program with the option "-" as	in
       blastall	- Note that the	input parameters (-i, -j, -input) should not
       be set directly by you: this module sets	them when you call one of the
       executable methods.


	 -p  Program Name [String]
	       Input should be one of "blastp",	"blastn", "blastx",
	       "tblastn", or "tblastx".
	 -d  Database [String] default = nr
	       The database specified must first be formatted with formatdb.
	       Multiple	database names (bracketed by quotations) will be accepted.
	       An example would	be -d "nr est"
	 -e  Expectation value (E) [Real] default = 10.0
	 -o  BLAST report Output File [File Out]  Optional,
		   default = ./blastreport.out ; set by
	 -S  Query strands to search against database (for blast[nx], and tblastx). 3 is both, 1 is top, 2 is bottom [Integer]
		   default = 3

       Blastpgp	(including Psiblast)

	 -j  is	the maximum number of rounds (default 1; i.e., regular BLAST)
	 -h  is	the e-value threshold for including sequences in the
		   score matrix	model (default 0.001)
	 -c  is	the "constant" used in the pseudocount formula specified in the	paper (default 10)
	 -B  Multiple alignment	file for PSI-BLAST "jump start mode"  Optional
	 -Q  Output File for PSI-BLAST Matrix in ASCII [File Out]  Optional


	 -d  Database [String] default = (none - you must specify a database)
	       The database specified must first be formatted with formatdb.
	       Multiple	database names (bracketed by quotations) will be accepted.
	       An example would	be -d "Cog Smart"
	 -e  Expectation value (E) [Real] default = 10.0
	 -o  BLAST report Output File [File Out]  Optional,
		   default = ./blastreport.out ; set by


	 -p  Program name: blastp, blastn, blastx. For blastx 1st argument should be nucleotide	[String]
	   default = blastp
	 -o  alignment output file [File Out] default =	stdout
	 -e  Expectation value (E) [Real]  default = 10.0
	 -S  Query strands to search against database (blastn only).  3	is both, 1 is top, 2 is	bottom [Integer]
	   default = 3


	 -p Program Name [String]
	       Input should be one of "wublastp", "wublastn", "wublastx",
	       "wutblastn", or "wutblastx".
	 -d  Database [String] default = nr
	       The database specified must first be formatted with xdformat.
	 -E  Expectation value (E) [Real] default = 10.0
	 -o  BLAST report Output File [File Out]  Optional,
		   default = ./blastreport.out ; set by

	Title	: executable
	Usage	: my $exe = $blastfactory->executable('blastall');
	Function: Finds	the full path to the executable
	Returns	: string representing the full path to the exe
	Args	: [optional] name of executable	to set path to
		  [optional] boolean flag whether or not warn when exe is not found

	Title	: program_dir
	Usage	: my $dir = $factory->program_dir();
	Function: Abstract get method for dir of program.
	Returns	: string representing program directory
	Args	: none

	Title	:  _setinput
	Usage	:  Internal function, not to be	called directly
	Function:   Create input file(s) for Blast executable
	Example	:
	Returns	: name of file containing Blast	data input
	Args	: Seq object reference or input	file name

Bio::Tools::Run::WrapperBase methods
	Title	: no_param_checks
	Usage	: $obj->no_param_checks($newval)
	Function: Boolean flag as to whether or	not we should
		  trust	the sanity checks for parameter	values
	Returns	: value	of no_param_checks
	Args	: newvalue (optional)

	Title	: save_tempfiles
	Usage	: $obj->save_tempfiles($newval)
	Returns	: value	of save_tempfiles
	Args	: newvalue (optional)

	Title	: outfile_name
	Usage	: my $outfile =	$tcoffee->outfile_name();
	Function: Get/Set the name of the output file for this run
		  (if you wanted to do something special)
	Returns	: string
	Args	: [optional] string to set value to

	Title	: tempdir
	Usage	: my $tmpdir = $self->tempdir();
	Function: Retrieve a temporary directory name (which is	created)
	Returns	: string which is the name of the temporary directory
	Args	: none

	Title	: cleanup
	Usage	: $tcoffee->cleanup();
	Function: Will cleanup the tempdir directory after a PAML run
	Returns	: none
	Args	: none

	Title	: io
	Usage	: $obj->io($newval)
	Function:  Gets	a Bio::Root::IO	object
	Returns	: Bio::Root::IO
	Args	: none

perl v5.32.1			  2021-03-0Bio::Tools::Run::StandAloneBlast(3)

NAME | SYNOPSIS | DESCRIPTION | FEEDBACK | AUTHOR - Peter Schattner | MAINTAINER - Torsten Seemann | CONTRIBUTORS | APPENDIX | Bio::Tools::Run::WrapperBase methods

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