Install and load multiple R packages at once

ipak.R

ipak <- function(pkg){
  new.pkg <- pkg[!(pkg %in% installed.packages()[, "Package"])]
  if (length(new.pkg))
    install.packages(new.pkg, dependencies = TRUE)
  # if install fails, try bioconductor
  new.pkg <- pkg[!(pkg %in% installed.packages()[, "Package"])]
  if (length(new.pkg)){
    if (! any(grep("BiocInstaller", search()))){
      source("https://bioconductor.org/biocLite.R")
      library(BiocInstaller)
    }
    biocLite(new.pkg, ask=F)
  }
  sapply(pkg, require, character.only = TRUE)
}

# to load:
# install.packages("devtools")
# library(devtools)
# source_url("https://gist.github.com/achateigner/f7948d43f34c1d1bcd83097036338601/raw/ipak.R")

I forked the stevenworthington's ipak, and added the automatic installation from bioconductor when a package is not found on CRAN.