Bus tracker

bustracker.r

library(XML)
library(data.table)
library(ggplot2)
library(ggmap)

args <- commandArgs(trailingOnly = T)

cat(args)

x <- readLines('http://realtime.lextran.com/InfoPoint/map/GetVehicleXml.ashx?RouteId=3')

xm <- xmlTreeParse(x, useInternalNodes = T)

vs <- getNodeSet(xm, '/vehicles/vehicle')

vehicles <- data.table(lat = as.numeric(sapply(vs, function(v) xmlGetAttr(v, 'lat'))),
                       long = as.numeric(sapply(vs, function(v) xmlGetAttr(v, 'lng'))),
                       name = sapply(vs, function(v) xmlGetAttr(v, 'name')))

lexmap <- qmap('Lexington, KY', zoom = 12, source = 'stamen', maptype = 'toner')
g <- lexmap + geom_point(data = vehicles, aes(x=long, y = lat, color = name), size = 10, alpha = 0.8)

png('busplot.png')
print(g)
dev.off()