NEWS

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treebalance 1.2.2 (2026-10-01)

• Changed results and return types: The Wedderburn-Etherington numbers in wedEth are now stored exactly as big integers (bigz, package gmp). Previously they were stored as double, which made them inexact from n = 50 and infinite from n = 793 on. As a consequence, furnasI(), furnasI_inv(), treenumber(), treenumber_inv() and getfurranks() now compute exactly for all trees with up to 2545 leaves; previously they silently returned wrong results for n >= 51. we_eth() now returns bigz by default.
• Changed results and return types: colPlaLab() now computes the Colijn-Plazzotta rank exactly and returns it as bigz by default; previously the ranks were wrong from n = 10 and infinite from n = 14 on. colPlaLab_inv() and cPL_inv() now also compute exactly.
• New argument type = "double" in we_eth(), furnasI(), treenumber() and colPlaLab() to obtain the result as double. It is only available as long as all values can be represented exactly (n <= 48, n <= 47 and n <= 9, respectively); otherwise the functions stop.
• furnasI_inv(), treenumber_inv(), colPlaLab_inv() and cPL_inv() accept the rank as bigz, character or double (the latter up to 2^53).
• Changed results: collesslikeI(dissim = "mdm") now computes the mean deviation from the median as documented. Previously the sum instead of the mean was returned, i.e. the balance value of every vertex was multiplied by its number of children.
• rQuartetI() now takes the shape value q0 into account (previously it was ignored, so results were only correct for q0 = 0) and checks that shapeVal has exactly 5 entries.
• B1I(), totCophI() and areaPerPairI() now return 0 (resp. the correct value) for star trees instead of NA.
• collessI(method = "corrected") now returns 0 for n = 2 as documented instead of NaN.
• is_binary() now returns FALSE instead of NULL for non-binary trees, so the binary-only functions show their intended error message.
• collesslikeI() now also accepts functions for f.size and dissim directly, not only their names as strings (needed e.g. for functions defined within another function or package).
• B2I() and sShapeI() now stop for the invalid logarithm base 1 (and sShapeI() also for non-positive bases) instead of returning Inf/NaN.
• tree_merge() now also works for trees with edge lengths (previously it failed with "tree 'x' has no root edge") and keeps tip labels and edge lengths when two single leaves are merged.
• furnasI_inv() and treenumber_inv() now also work when treebalance is not attached, e.g. when used from within another package.
• Updated the citation to the published book "Tree Balance Indices -- A Comprehensive Survey" (Springer, 2023).

treebalance 1.2.0 (2023-12-14)

• Added modified maximum difference in width.
• Changed FurnasI such that it can deal with larger numbers.

treebalance 1.1.0 (2021-10-17)

• Added a NEWS.md file to track changes to the package.
• Added arXiv identifier of "Tree balance indices: a comprehensive survey" to DESCRIPTION.
• Corrected a mistake in the function furnasI_inv().