Editing Distance matrix (section)

===== Neighbor joining =====
Neighbor is a bottom-up clustering method. It takes a distance matrix specifying the distance between each pair of sequences. The algorithm starts with a completely unresolved tree, whose topology corresponds to that of a [[star network]], and iterates over the following steps until the tree is completely resolved and all branch lengths are known:

# Based on the current distance matrix calculate the matrix (defined below).
# Find the pair of distinct taxa i and j (i.e. with) for which has its lowest value. These taxa are joined to a newly created node, which is connected to the central node. 
# Calculate the distance from each of the [[Taxon|taxa]] in the pair to this new node.
# Calculate the distance from each of the taxa outside of this pair to the new node.
# Start the algorithm again, replacing the pair of joined neighbors with the new node and using the distances calculated in the previous step.<ref>{{Cite journal |last=Saitou |first=Naruya |date=1987 |title=The neighbor-joining method: A new method for reconstructing phylogenetic trees |url=https://academic.oup.com/mbe/article/4/4/406/1029664?login=false |journal=Molecular Biology and Evolution |volume=4|issue=4 |pages=406–425 |doi=10.1093/oxfordjournals.molbev.a040454 |pmid=3447015 |doi-access=free }}</ref>