rCTA

rCTA is an R interfact to access the APIs of Chicago Transit Authority(CTA) in order to get real-time information of buses and help users make empowered decisions about their trips.The APIs include Bus Tracker API and Customer Alerts API. Check out the documentations here:

Bus Tracker API Documentation

Customer Alerts API Documentation

APIs in rCTA

There are two API contained in this package:

  • Bus Tracker API: This API allows developers to request and retrieve the real-time information of buses. Data available through the API includes:
    • Vehicle locations
    • Route data (route lists, stop lists geo-positional route definitions, etc.)
    • Prediction Data
    • Service Bulletins
  • Customer Alerts API: This API allows developers to get detailed information about current alerts. Data available through the API includes:
    • Route status
    • Detailed alerts

API Authentication

You will need an API key to interact with Bus Tracker API on every requrest (Customer Alerts API does not need authentication). To become authorized, follow the instructions below:

1. Get an API key

  • Sign up and activate your account at Bus Tracker Sign up.
  • Sign into Bus Tracker Sign in.
  • Choose on My Account in the upper right-hand corner of the page.
  • Follow the link under “Developer API” to apply.

2. Store your API key

Once you obtain an API key, we encourage you to store it in the .Renviron file which is loaded during R’s startup.

First, find your R Home directory:

R.home(component = "home")

Then, open the the file Renviron.site and add the Bus Tracker API keys with the following lines:

BUS_CLIENT_KEY = THE_API_KEY_HERE

Installation and Setup

You can install the released version of rCTA from GitHub with:

devtools::install_github("ytingc/rCTA")

Then, you can load rCTA package to play with:

library(rCTA)

Features of rCTA pacakge

Search Routes

Get routes of bus number 5.

result <-get_route(bus = 5)
knitr::kable(head(result))
bus_number route_name
5 South Shore Night Bus

Search Direction

Get direction of bus number 126.

result <- get_direction(bus = 126)
knitr::kable(head(result))
dir
Eastbound
Westbound

Search Stops

Search for stop information. Useful when stop_id is unknown.It is not case sensitive. For example:

result <- lookupstop(bus = 1, stopname = "Michigan", dir = "southbound")
knitr::kable(head(result, 10))
bus_num direction stop_id stop_name lat lon
1 Southbound 1606 3000 S Michigan 41.84045 -87.62356
1 Southbound 1590 Michigan & 11th Street 41.86892 -87.62394
1 Southbound 1592 Michigan & 13th Street 41.86553 -87.62399
1 Southbound 1593 Michigan & 14th Street 41.86391 -87.62414
1 Southbound 1595 Michigan & 16th Street 41.85997 -87.62403
1 Southbound 1596 Michigan & 18th Street 41.85763 -87.62405
1 Southbound 1598 Michigan & 21st Street 41.85404 -87.62384
1 Southbound 16014 Michigan & 23rd Street 41.85130 -87.62383
1 Southbound 17243 Michigan & 24th Street 41.84946 -87.62383
1 Southbound 1602 Michigan & 25th Street 41.84723 -87.62372

Set up favorite route

Get real-time information of your favorite route. You can obtain estimated arrival time, waiting time, travel time, delay and alert message. It also allows users to collect and save the real-time information for a given period in a data frame through calling the function periodically. Note that it is a real-time data, it may generate error message“No service scheduled” when you request at a time out of operation. Or, it may generate error message “No arrival times” if the system has not been updated yet, since the CTA system update the data about once per minute.

result <- myfavrt(bus = 126, start_id = 36, end_id = 60, interval= 60, times = 5)
knitr::kable(head(result))
no. current_time bus_num start_stop_id start_stop_name end_stop_id end_stop_name wait_time_in_min departurel_time arrival_time travel_time_in_min delay status
126 20181217 12:22 126 36 Jackson + 2609 West Alley 60 Jackson + Aberdeen 5 20181217 12:27 20181217 12:39 12 mins FALSE Planned Reroute
126 20181217 12:23 126 36 Jackson + 2609 West Alley 60 Jackson + Aberdeen 4 20181217 12:28 20181217 12:39 11 mins FALSE Planned Reroute
126 20181217 12:24 126 36 Jackson + 2609 West Alley 60 Jackson + Aberdeen 4 20181217 12:28 20181217 12:39 11 mins FALSE Planned Reroute
126 20181217 12:25 126 36 Jackson + 2609 West Alley 60 Jackson + Aberdeen 3 20181217 12:29 20181217 12:40 11 mins FALSE Planned Reroute
126 20181217 12:26 126 36 Jackson + 2609 West Alley 60 Jackson + Aberdeen 2 20181217 12:28 20181217 12:39 11 mins FALSE Planned Reroute

Get Alerts

Get the alerts of bus number 8.

result <-get_alert(bus = 8)
knitr::kable(head(result))
Headline ShortDescription EventStart EventEnd
New Schedules in Effect Beginning Sunday, December 16, updated schedules went into effect for several bus routes. 2018-12-16 NA

Get an Overview of Current Bus Alerts

Obtain an overview of current alerts of all CTA buses through a summary table that provide the count of each type of alerts.

result <- alertstat()
knitr::kable(head(result), col.names = c("Type", "Frequency"))
Type Frequency
Bus Stop Note 2
Bus Stop Relocation 8
Planned Reroute 15
Service Change 13
Special Note 136

Vignettes

Detailed application of functions can be otained through the following:

# search for general information
vignette("lookup_info", package = "rCTA")
# set up my favorite route
vignette("setup_myfavorite", package = "rCTA")
# get information of alerts
vignette("Alert_info", package = "rCTA")

Contact

yc3539@columbia.edu or open GitHub issue.