Blast Xml Document Iterations

When running BLAST with one sequence against a sequence database there is only one iteration in the <Iteration> element, as in the value of Iteration_iter-num is one. For example:<?xml version="1.0"?><!DOCTYPE BlastOutput PUBLIC "-//NCBI//NCBI BlastOutput/EN" "http://www.ncbi.nlm.nih.gov/dtd/NCBI_BlastOutput.dtd"><BlastOutput><BlastOutput_program>blastn</BlastOutput_program><BlastOutput_version>BLASTN 2.2.28+</BlastOutput_version><BlastOutput_reference>Zheng Zhang, Scott Schwartz, Lukas Wagner, and Webb Miller (2000), &quot;A greedy algorithm for aligning DNA sequences&quot;, J Comput Biol 2000; 7(1-2):203-14.</BlastOutput_reference><BlastOutput_db>nr</BlastOutput_db><BlastOutput_query-ID>42945</BlastOutput_query-ID><BlastOutput_query-def>No definition line</BlastOutput_query-def><BlastOutput_query-len>1440</BlastOutput_query-len><BlastOutput_param><Parameters><Parameters_expect>10</Parameters_expect><Parameters_sc-match>1</Parameters_sc-match><Parameters_sc-mismatch>-2</Parameters_sc-mismatch><Parameters_gap-open>0</Parameters_gap-open><Parameters_gap-extend>0</Parameters_gap-extend><Parameters_filter>L;m;</Parameters_filter></Parameters></BlastOutput ...