# ipak function: install and load multiple R packages.
# Check to see if packages are installed. Install them if they are not.
# Optionally, load them into the R session.

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

# usage
packages <- c(
    "assertthat", "testthat", "devtools", "dplyr",
    "readxl", "reshape2", "ggplot2", "stringr", # Hadley-verse
    "jsonlite", "knitr", "yaml", "xml2", "lubridate", # Utils
    "lamW", "bbmle", "boot", "emdbook", # FRAIR
    "sp", "spatial", "gstat", "maps", "maptools", "leaflet", # GIS
    "MASS", "vegan", "car", "nortest", # Statistics
    "RColorBrewer", "cowplot", "ggthemes", # Plotting
    "fortunes" # Fun
)

ipak(packages, load = FALSE)