# changes, 1.18

• packages that have been published and certified:
• PhylogeneticTrees, a package by Nathaniel Bushek, Ruth Davidson, Elizabeth Gross, Pamela Harris, Robert Krone, Colby Long, AJ Stewart, and Robert Walker for invariants for group-based phylogenetic models, has been published.
• GradedLieAlgebras, a package by Clas Löfwall and Samuel Lundqvist for computations in graded Lie algebras, has been published.
• RelativeCanonicalResolution, a package by Christian Bopp and Michael Hoff for computation of the relative canonical resolution for g-nodal canonical curves with a fixed $g^1_k$, has been published.
• FrobeniusThresholds, a package by Juliette Bruce, Daniel Hernández, Karl Schwede, Dan Smolkin, Pedro Teixeira, and Emily Witt, for calculations of F-thresholds, has been published.
• new packages:
• AssociativeAlgebras, a package by Frank Moore and Mike Stillman for noncommutative algebra, has been added.
• RationalPoints2, a package by Jieao Song for finding rational points on a variety, has been added.
• SuperLinearAlgebra, a package by Fereshteh Bahadorykhalily and Fatemeh Tarashi Kashani for computing with supermatrices, has been added.
• SubalgebraBases, a package by Michael Burr, Oliver Clarke, Timothy Duff, Jackson Leaman, Nathan Nichols, Elise Walker, Mike Stillman, and Harrison Tsai, for computing canonical subalgebra bases, has been added.
• AInfinity, a package by David Eisenbud and Mike Stillman for A-infinity structures on free resolutions, has been added.
• LinearTruncations, a package by Lauren Cranton Heller, David Eisenbud, and Navid Nemati for finding multigraded truncations that give linear resolutions, has been added.
• improved packages:
• The package NumericalSchubertCalculus has been improved: several functions and options were added for user convenience. Output formats, verbosity, and documentation were greatly improved.
• The package VirtualResolutions has been improved: a new strategy using a significantly faster algorithm has been added for the multigradedRegularity function.
• The package NoetherianOperators has been improved: the DiffOp type has been reworked, and support for Noetherian operators and differential primary decompositions of modules has been added.
• Several packages (Chordal, Graphs, Markov, and Posets) that generate and display visualizations of mathematical objects using external image viewers have been modified so that they no longer require package-specific configuration of these viewers. Instead, show is used, which opens the images using the system default viewer (using open on macOS and xdg-open on Linux).