Figure 4
From: biobambam: tools for read pair collation based algorithms on BAM files
Collation Hash Table H . The hash table H used for collation is composed of three components. The ring buffer R stores alignment data. In the picture it contains three alignments A i ,A j and A k . The insert pointer r is situated just after the alignment A j . The hash table P stores pointers into R, where the position of the respective pointers is given by a hash value computed from the name of the stored alignment. The B-tree B stores the starting positions of alignments in R in sorted order.