R Markdown and Leaflet

Introduction

Leaflet is one of the most popular Javascript libraries for creating interactive maps. The leaflet R package allows you to create your own leaflet maps without needing to know any Javascript!

In this smnall project, I will show all the location of 10 Universitiy of California with customized logo with corresponding popup logos and main webstite.

Load necessary libraries

library(leaflet)
library(dplyr)

Create Data Frame with campus name and exact location (lattitude and longitute)

UCLatLong <- data.frame(
    campus = c("UCI","UCLA","UCB","UCSD","UCD",
               "UCSB","UCR","UCM","UCSC","UCSF"),
    lat = c(33.6482,34.0702,37.8719,32.8780,38.5382,
            34.4140,33.9737,37.3642,36.9741,37.7631),
    lng = c(-117.8420,-118.4453,-122.2594,-117.2347,-121.7617,
            -119.8489,-117.3281,-120.4255,-122.0308,-122.4578))

Create specific icon list with customize size

w = 60
h = 30
UCIcons <- iconList(
    makeIcon(iconUrl = "./logos/UCI.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCLA.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCB.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCSD.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCD.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCSB.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCR.png", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCM.jpg", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCSC.jpg", iconWidth = w, iconHeight = h),
    makeIcon(iconUrl = "./logos/UCSF.png", iconWidth = w, iconHeight = h)
)

Create PopUp parameters with correspoinding website.

UCSites <- c(
  "<a href='http://www.uci.edu/'>UC Irvine</a>",
  "<a href='http://www.ucla.edu/'>UCLA</a>",
  "<a href='http://www.berkeley.edu/'>UC Berkerly</a>",
  "<a href='http://www.ucsd.edu/'>UCSD</a>",
  "<a href='http://www.ucdavis.edu/'>UC Davis</a>",
  "<a href='http://www.ucsb.edu/'>UCSB</a>",
  "<a href='http://www.ucr.edu/'>UC Riverside</a>",
  "<a href='http://www.ucmerced.edu/'>UC Merced</a>",
  "<a href='http://www.ucsc.edu/'>UCSC</a>",
  "<a href='http://www.ucsf.edu/'>UCSF</a>"
)

let’ see how all UC campuses are distributed in California.

UCLatLong %>% 
    leaflet() %>% 
    addTiles() %>%
    addMarkers(icon = UCIcons, popup = UCSites)

## Assuming "lng" and "lat" are longitude and latitude, respectively