We will plot the locations of all colleges in the United States. The data is downloaded from the website https://collegescorecard.ed.gov/data/
temp <- tempfile()
url <- "https://ed-public-download.apps.cloud.gov/downloads/CollegeScorecard_Raw_Data.zip"
download.file(url,temp,method="curl")
data <- read.csv(unz(temp, "CollegeScorecard_Raw_Data/MERGED2014_15_PP.csv"), na.strings = c("NA","NULL","#DIV/0!",""), stringsAsFactors = FALSE)
unlink(temp)library(leaflet)
df <- data[,c('LATITUDE','LONGITUDE','INSTNM','INSTURL')]
df <- df[complete.cases(df),]
df$INSTURL <- ifelse(substring(df$INSTURL,1,4)== 'www.',paste0("http://", df$INSTURL), paste0("http://www.", df$INSTURL))
df$popupVec <- paste0("<a href='", df$INSTURL, "'>", df$INSTNM, "</a>")
df[,c('LATITUDE','LONGITUDE')] %>% leaflet() %>% setView(lng = -98.583, lat = 39.833, zoom = 2) %>% addTiles() %>% addMarkers(popup = df[, c('popupVec')], clusterOptions = markerClusterOptions())