calculating the coverage percentage from blast8

Question

[EVR]

Hi,

I used blat to find the similar transcripts between two transcriptomes. I outputted the result in blast8 tabular format which includes the following fields
Query_id,Subject_id,Percent_identity,alignment_length,mismatches,gap_openings,q._start,q_end,s_start,s_end,e-value,bit score

Based on these data how can calculate the query coverage percentage? Any guidance would be highly appreciated

[Prakki Rama]

You should add one more column, total length of the query sequence. Then calculate alignmentLength/total_query_seq_length.