Constructing Adjacency Matrices Based on Spatial and Feature Similarity R package adjoin version 0.1.0 Constructs sparse adjacency matrices from spatial coordinates, feature measurements, class labels, and temporal indices. Supports nearest-neighbor graphs, heat-kernel weights, graph Laplacians, diffusion operators, and bilateral smoothers for graph-based data analysis, following spectral graph methods in von Luxburg (2007) <doi:10.1007/s11222-007-9033-z>, diffusion maps in Coifman and Lafon (2006) <doi:10.1016/j.acha.2006.04.006>, and bilateral filtering in Tomasi and Manduchi (1998) <doi:10.1109/ICCV.1998.710815>. Software Depends: R (>= 4.0.0) Imports: Rcpp (>= 0.11.3), Matrix, assertthat, Rnanoflann, chk, RSpectra, igraph, parallel, stats, methods, utils, mgcv, proxy, corpcor LinkingTo: Rcpp, RcppArmadillo Suggests: testthat (>= 3.0.0), RcppHNSW (>= 0.6.0), knitr, rmarkdown, furrr, crayon, ggplot2 Bradley R. Buchsbaum <brad.buchsbaum@gmail.com> Comprehensive R Archive Network (CRAN) Bradley R. Buchsbaum [aut, cre] (ORCID: <https://orcid.org/0000-0002-1108-4866>) MIT + file LICENSE (https://CRAN.R-project.org/package=adjoin/LICENSE) 2026-04-21 application/tgz https://CRAN.R-project.org/package=adjoin doi:10.32614/CRAN.package.adjoin