Database-Backed Matrix Classes and Operations R package dbMatrix version 0.1.0 Provides S4 classes and methods for storing dense and sparse matrices in 'DuckDB' databases. The package supports constructing database-backed matrices from base R and 'Matrix' objects, extracting slices and summaries, performing arithmetic and selected linear algebra operations, and materializing results for larger-than-memory workflows. It integrates with 'dbProject' to keep database paths, live connections, and lazy matrix tables synchronized across interactive analyses. Software Depends: R (>= 4.1.0) Imports: Matrix (>= 1.6-5), MatrixGenerics (>= 1.12.3), methods, DBI, dplyr, dbplyr, duckdb (>= 1.4.0), data.table (>= 1.12.2), glue, bit64, cli, Rcpp, arrow, nanoarrow, dbProject, rlang LinkingTo: Rcpp, RcppEigen, RSpectra, nanoarrow Suggests: knitr, rmarkdown, testthat (>= 3.0.0), irlba, crayon, R.utils, checkmate, reticulate, sparseMatrixStats, RSpectra Edward C. Ruiz <ecr7407@gmail.com> Comprehensive R Archive Network (CRAN) Edward C. Ruiz [aut, cre] (ORCID: <https://orcid.org/0000-0002-9174-5387>), Jiaji George Chen [aut], Ruben Dries [aut] GPL-3 2026-05-19 application/tgz https://CRAN.R-project.org/package=dbMatrix doi:10.32614/CRAN.package.dbMatrix