Projection Pursuit Classification Tree Extensions R package PPtreeExt version 0.1.0 Implements extensions to the projection pursuit tree algorithm for supervised classification, see Lee, Y. (2013), <doi:10.1214/13-EJS810> and Lee, E-K. (2018) <doi:10.18637/jss.v083.i08>. The algorithm is changed in two ways: improving prediction boundaries by modifying the choice of split points-through class subsetting; and increasing flexibility by allowing multiple splits per group. Software Depends: R (>= 4.3.0) Imports: Rcpp (>= 1.1.0), ggplot2, shiny, MASS, gridExtra, MixSim, PPtreeViz LinkingTo: Rcpp,RcppArmadillo Suggests: knitr, randomForest, rpart, GGally, RColorBrewer, roxygen2 (>= 7.3.0), rmarkdown, rsample Natalia da Silva <natalia.dasilva@fcea.edu.uy> Comprehensive R Archive Network (CRAN) Natalia da Silva [aut, cre] (ORCID: <https://orcid.org/0000-0002-6031-7451>), Dianne Cook [aut], Eun-Kyung Lee [aut] GPL (>= 2) 2026-02-06 application/tgz https://CRAN.R-project.org/package=PPtreeExt doi:10.32614/CRAN.package.PPtreeExt