A dendrogram is a tree diagram frequently used to illustrate the arrangement of the clusters produced by a clustering algorithm (see cluster analysis). Dendrograms are often used in computational biology to illustrate the clustering of genes.Dendron is the Greek word for tree (Greek: tree, tree-like structure; trees).For a clustering example, suppose this data is to be clustered using euclidean distance as the distance metric.
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a diagram that shows a hierarchy and the relation of subsets in a structure. It branches like a tree and is usually read downwards from the main trunk.