# CRAN packages required for influx_si
preq=c("nnls", "rmumps", "arrApply", "slam", "limSolve", "multbxxc")
# check what is already installed
iinst=sapply(preq, requireNamespace, quietly = TRUE)
repos=getOptions("repos")
repos=if (!length(repos) || repos == "@CRAN@") "https://cloud.r-project.org/" else repos
# install lacking packages
plack=preq[!iinst]
if (length(plack))
   install.packages(plack, repos=repos)
# update already present
pold=preq[iinst]
if (length(pold))
   update.packages(oldPkgs=pold, repos=repos, ask=FALSE)
