Allright, I understand the argument passed to blast in order to specify actual size of the DB, instead of letting blast assume size from the chunk it is running against. Since I'm playing with this for the moment, I was wondering what solution people used when users asked for blast jobs against set of DBs, each of these being splitted across the nodes. Of course you just need to add the size, but the point was : is there an existing tool ? Your previous message seemt to indicate that you were doing some "posterior" statistical reworking. For the moment I am using an old version of blastmerge.c (2003) which is able to merge regular text blast quite nicely, but unfortunately is not meant to merge blast-chunks of different DBs, This is not only a theoretical problem, users *do* run blasts jobs against mixed sets of DB, for example against public_embl_est_pln and *my_secret_private_hot_db* altogether I've been planning on rewriting a "blastmerge" by using blast-chunks in XML-output, which would in turn be extremely EZ to merge altogether, my main problem being that I need to produce regular text-blast output (and stats), and I am entirely *clueless* regarding this issue. Anyone experimented with MPI-Blast knows how this mixed DB stats problem is managed in MPI-blast ? Anyone has any clue regarding a "Blast-XML-Output" to "Blast-text-output" converter ? in bioperl ? =============================================== David Coornaert (dcoorna at dbm.ulb.ac.be) Belgian Embnet Node (http://www.be.embnet.org) Université Libre de Bruxelles Laboratoire de Bioinformatique 12, Rue des Professeurs Jeener & Brachet 6041 Gosselies BELGIQUE Tél: +3226509975 Fax: +3226509998 =============================================== Tim Cutts wrote: > > On 26 Sep 2005, at 10:22 am, david coornaert wrote: > >> What are you using to merge the outputs ? (and to manage the stats...) >> > > Hey, I'm just the sysadmin. :-) I think the output is merged > usually by perl code, using the BioPerl BLAST parsers. Stats can be > dealt with, I understand, in BLAST itself; there's a parameter to > tell it actually how large the total database is, not just the > segment it's currently running against. There are people on this > list far better qualified than I to give you the details... > > Tim > >