Install and load multiple R packages at once

ipak_spatial.R

# ipak function: install and load multiple R packages.
# check to see if packages are installed. Install them if they are not, then load them into the R session.
# originally from https://gist.github.com/stevenworthington/3178163, which did not specify a license

ipak <- function(pkg){
    new.pkg <- pkg[!(pkg %in% installed.packages()[, "Package"])]
    if (length(new.pkg)) 
        install.packages(new.pkg, dependencies = TRUE)
    sapply(pkg, require, character.only = TRUE)
}

# Run the lines below to install spatial packages from workshop
# If you are on Linux or Mac, you may need system libraries installed before installing some of these packages
# Use more than one core to speed up installs. For example, if you have 4 cores on your machine:
options(Ncpus=4)

packages <- c("rgdal", "rgeos", "sp", "sf", "mapview", "units", "dplyr", "devtools", "mapview", "data.table", 
              "rmapshaper", "osmdata", "rnaturalearth", "raster", "ncdf4")
ipak(packages)
devtools::install_github("tidyverse/ggplot2") # development version for sf support