Hi Lucas Thank you so much about your opnion. I will test dBlast, but I think ( I read the paper) the solution is equal of mpiBLAST, it is, one patch to NCBI BLAST. well I'm studing about this issue, then any other thing please tell me. So I will wait the opnion from other users of list. By Daniel Xavier ----- Mensagem original ---- De: Lucas Carey <lcarey at odd.bio.sunysb.edu> Para: HPC in Bioinformatics <bioclusters at bioinformatics.org> Enviadas: Segunda-feira, 27 de Novembro de 2006 14:05:47 Assunto: Re: [Bioclusters] split database with blast Hi Daniel, It is non-trivial to get correct effective database sizes with NCBI BLAST, as it involves processing both query sequences and database sequences. You're best bet is to use a package that can split the databases and return correct e-values. mpiBLAST is one, but dBlast is another if for some unfathomable reason you don't like mpiBLAST. However, depending on what you're doing, e-value differences may not matter. In my personal opinion, there is no difference between e-36 and e-40, so the differences you are talking about are negligible. -Lucas On Tuesday, November 21, 2006 at 15:41 -0800, Daniel Xavier de Sousa wrote: > > > Hi for all, > > I need some help about Parallel BLAST. I will bee happy if anyone help me. > I have worked with parallel BLAST using split database. > > I don?t have problem to execute on part of database and statistics values when > use WUBLAST, because use DBRECMAX and DBRECMIN parameters and I > execute Blast like virtual split database, get just the piece of all > database, and the e-value get right. > > But I really want do everything work in NCBI_BLAST. I know the solution of mpiBLAST > and the list of GI number file. But, these solutions aren?t so good. > The first because the source of BLAST have to change. And the second, > because require that you use GI numbers in the FASTA identifier. > > So, my question is: > > 1) Somebody > knows some else solution to run process blast on split database, and > not changes the e-value with relation to run whole database? > > If not, the difference between e-value with whole database and part of database (using the parameter ?z and ?Y of ncbi_blast) is very important? > > Example, I processed one sequence with whole database and just part of database, using parameter ?z, the result was: > > (evalue)NR (evalue) NR/2 using ?z > SeqQuery Seq1DB 4e-66 6e-66 > SeqQuery Seq2DB 4e-38 5e-38 > > This difference is relevant? > Thanks, > > Daniel Xavier ? PUC ? Rio de Janeiro - Brazil _______________________________________________ Bioclusters maillist - Bioclusters at bioinformatics.org https://bioinformatics.org/mailman/listinfo/bioclusters _______________________________________________________ Novidade no Yahoo! Mail: receba alertas de novas mensagens no seu celular. Registre seu aparelho agora! http://br.mobile.yahoo.com/mailalertas/