The 'rgr' package for the R Open Source statistical computing and graphics environment - a tool to support geochemical data interpretation

The development of interactive computer graphics to support applied geochemistry over the last 40 years at the Geological Survey of Canada (GSC) is briefly discussed. The loss of an interactive computing environment, IDEAS, in 1995 based on a DEC VAX computer largely negated nine years of work, though the experience gained was invaluable. The availability of the commercial S-PLUS package in a Windows PC environment led to the redevelopment of most of the functionality of IDEAS in the S language for statistical analysis and graphics. In 2006 a request from a sister federal government department for the S-PLUS software led to the decision to translate the S functions into R, an Open-Source implementation of the S language, and therefore free to the user. Since that time all development has been in R, resulting in the 2007 release to the public of a package of tools, 'rgr', to assist applied geochemists in interpreting their data. Subsequently, 'rgr' has been updated and extended. The move to Open Source R and the release of the 'rgr' package on the Comprehensive R Archival Network (CRAN) has made these tools, and their documentation, available for Windows, Unix and Mac computing environments. The paper outlines the features of 'rgr' and illustrates key graphic and tabular displays. Its functionality is reviewed in the context of earlier GSC interactive graphics packages.