trestat

Treestat is a software tool and library designed for the quantitative analysis of tree-structured data. It is used across disciplines such as evolutionary biology, linguistics, and computer science to summarize, compare, and visualize the shapes and branch-length distributions of trees. Treestat typically accepts standard tree formats and can operate on single trees or collections of trees.

Treestat can ingest formats such as Newick, Nexus, NeXML, and JSON, and computes a range of statistics that describe topology, branch lengths, and temporal dynamics. Common outputs include measures of tree balance and imbalance, distribution of node depths, counts of cherries and other clades, and lineage-through-time plots. The tool generally supports exporting results to CSV or JSON for downstream analysis and can generate simple visualizations to illustrate tree shape.

Treestat exists in several independent implementations and is commonly distributed as open-source software or libraries. It can be used as a stand-alone command-line utility or integrated into larger analysis pipelines through language bindings for Python or R, often interfacing with broader ecosystems such as Biopython, DendroPy, or the ETE Toolkit.

In practice, trestat is used to compare sets of trees produced by different inference methods, models, or datasets, to assess sampling adequacy, and to explore hypotheses about evolutionary or linguistic processes that influence tree shape. Related tools and libraries include the ETE Toolkit, DendroPy, and Phylo in Biopython.