Changes in version 1.0 PTT 1.0 is the first official release of the package. Models - Provides adaptive Pólya tree (APT), Markov APT, and optional Pólya tree (OPT) models for Bayesian nonparametric density estimation. - Provides conditional APT and conditional OPT models for conditional-density estimation through recursive partitioning of the predictor space. - Supports univariate and multivariate observations on the unit hypercube or a data-adaptive standardized hyperrectangle. Inference and results - Uses exact forward-backward inference on finite recursive partition trees. - Computes log marginal likelihoods, posterior root shrinkage probabilities, posterior predictive densities, and hierarchical MAP partitions. - Generates posterior partition samples using R's random-number generator for reproducible simulation. - Reports predictive densities in the physical coordinates of the selected sample space. Package interface - Supplies documented R interfaces backed by registered C++ routines using Rcpp and RcppArmadillo. - Validates observations, prediction matrices, sample spaces, and model parameters before native computation. - Includes plotting utilities for two-dimensional partitions and ROC curves. - Includes package-level documentation, method references, citation metadata, API and numerical regression tests, and seven reproducible visual demos for marginal and conditional models in one and two dimensions.