Module banded 

Banded global (Needleman–Wunsch) alignment.

Restricts the Needleman–Wunsch dynamic program to a diagonal band of half-width band — only cells with |i − j| ≤ band are evaluated. For two sequences that are near-identical (small edit distance) this finds the optimal banded global alignment by touching only the O(n · band) cells inside the band; every cell outside the band is held at −∞ and can never lie on an optimal path. The score is therefore ≤ the unrestricted Needleman–Wunsch score, and equals it whenever the band is wide enough to contain an optimal path.

Functions

banded_align

Run banded global alignment of a against b.