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blast6out file

The blast6out option specifies an output file in a format compatible with the NCBI BLAST -m8 and NCBI BLAST+ -outfmt 6 formats. It is a tab-separated text file with one line per alignment. By convention I use the .b6 extension for files in this format. There are twelve fields, as shown in the table.
Field   Description
1   Query label.
2   Target (database sequence or cluster centroid) label.
3   Percent identity.
4   Alignment length.
5   Number of mismatches.
6   Number of gap opens.
7   Start position in query. Query coordinates start with 1 at the first base in the sequence as it appears in the input file. For translated searches (nucleotide queries, protein targets), query start<end for +ve frame and start>end for -ve frame.
8   End position in query.
9   Start position in target. Target coordinates start with 1 at the first base in sequence as it appears in the database. For untranslated nucleotide searches, target start<end for plus strand, start>end for a reverse-complement alignment.
10   End position in target.
11   E-value calculated using Karlin-Altschul statistics.
12   Bit score calculated using Karlin-Altschul statistics.