Just a small package that wraps the Fahrplan API of the German train company db. The main idea is to be able to cast your net a bit wider in cases when you are flexible to go on a different hour, day, or week.
Note
I do not have time to actively develop this package. It should be seen as a prototype. If you want to take it over as maintainer to develop it further, let me know.
You can install the development version of zugr like so (or with
remotes, but the cool kids use pak now 😁):
# install.packages("pak)
pak::pak("JBGruber/zugr")A journey that I take often is from Wiesbaden to Amsterdam. There are really fast connections between these cities, which is awsome! What is less great is trying to decide if I go Monday or Tuesday, on the weekend or during the week, or if I should rather go in a different week? If you’ve used the interface of bahn.de, you know these decisions require a lot of useless click-work. Well not anymore…
The first step is to get the station ID for the main stations in Wiesbaden and Amsterdam:
library(zugr)
wi <- search_station("Wiesbaden HBF")
wi
#> # A tibble: 10 × 2
#> name id
#> <chr> <chr>
#> 1 Wiesbaden Hbf A=1@O=Wiesbaden Hbf@X=8243729@Y=50070788@U=80@L=80002…
#> 2 Wiesbaden-Mainz-Kast A=1@O=Wiesbaden-Mainz-Kast@X=8283173@Y=50006578@U=80@…
#> 3 Wiesbaden-Auringen-M A=1@O=Wiesbaden-Auringen-M@X=8332092@Y=50113604@U=80@…
#> 4 Wiesbaden-Biebrich A=1@O=Wiesbaden-Biebrich@X=8236420@Y=50048827@U=80@L=…
#> 5 Wiesbaden-Erbenheim A=1@O=Wiesbaden-Erbenheim@X=8295048@Y=50054410@U=80@L…
#> 6 Wiesbaden Ost A=1@O=Wiesbaden Ost@X=8256295@Y=50041411@U=80@L=80064…
#> 7 Wiesbaden-Igstadt A=1@O=Wiesbaden-Igstadt@X=8325638@Y=50082582@U=80@L=8…
#> 8 Wiesbaden-Schierstein A=1@O=Wiesbaden-Schierstein@X=8194602@Y=50047587@U=80…
#> 9 Wiesbaden-Chausseehaus A=1@O=Wiesbaden-Chausseehaus@X=8168794@Y=50097765@U=8…
#> 10 Wiesbaden-Biebr. KD A=1@O=Wiesbaden-Biebr. KD@X=8236600@Y=50036234@U=80@L…The first one is what I need! Now Amsterdam. Here I don’t need as many options:
adam <- search_station("Amsterdam", n_res = 2)
adam
#> # A tibble: 2 × 2
#> name id
#> <chr> <chr>
#> 1 Amsterdam Centraal A=1@O=Amsterdam Centraal@X=4899427@Y=52379191@U=80…
#> 2 Amsterdam, Centaurusstraat A=2@O=Amsterdam, Centaurusstraat@X=4884163@Y=52414…Now I can make a search for next Tuesday Morning (as of writing this):
next_tuesday <- bahn_search(
from = wi$id[1],
to = adam$id[1],
start = "2024-02-06T05:00:00",
end = "2024-02-06T19:00:00"
)
next_tuesday
#> # A tibble: 28 × 6
#> id duration price changes start
#> <chr> <Duration> <dbl> <int> <dttm>
#> 1 12f92732_3 16140s (~4.48 hours) 79.9 1 2024-02-06 05:00:00
#> 2 b5b084ea_3 20460s (~5.68 hours) 85.9 2 2024-02-06 05:48:00
#> 3 c2154884_3 17400s (~4.83 hours) 99.9 1 2024-02-06 06:39:00
#> 4 29be3e05_3 20820s (~5.78 hours) 57.9 3 2024-02-06 06:48:00
#> 5 8f800bd9_3 22620s (~6.28 hours) 37.9 4 2024-02-06 06:48:00
#> 6 03e0ebdd_3 20820s (~5.78 hours) 83.9 4 2024-02-06 07:18:00
#> 7 a5c4f48e_3 20460s (~5.68 hours) 78.9 2 2024-02-06 07:48:00
#> 8 705c73ef_3 17400s (~4.83 hours) 89.9 1 2024-02-06 08:39:00
#> 9 73acf6a5_3 20820s (~5.78 hours) 83.9 3 2024-02-06 08:48:00
#> 10 6a9b423e_3 22620s (~6.28 hours) 47.9 5 2024-02-06 08:48:00
#> # ℹ 18 more rows
#> # ℹ 1 more variable: end <dttm>Note that the end parameter marks the time at which the train should
arrive at the latest, while start marks the earliest departure that
should be included in the results.
So what is the cheapest connection? Easy to see with some R commands
:smirk::
library(tidyverse)
next_tuesday |>
slice_min(price, n = 1) |>
select(-id)
#> # A tibble: 1 × 5
#> duration price changes start end
#> <Duration> <dbl> <int> <dttm> <dttm>
#> 1 22620s (~6.28 hours) 37.9 4 2024-02-06 06:48:00 2024-02-06 13:05:00With 5 connections and more than 6 hours, this is a rather terrible connections. It is cheap though. Let’s see s quick visualisation instead:
next_tuesday |>
# some connections include trains from different companies, the prices for
# these are not included
filter(!is.na(price),
!duplicated(start),
start < "2024-02-06 11:00:00") |> # exclude some connections for readability
ggplot(aes(x = start, y = price, label = changes, fill = duration)) +
geom_col() +
geom_text(aes(y = price / 2), colour = "white") +
scale_y_continuous(labels = function(x) paste0(x, "€")) +
scale_fill_gradient(labels = function(x) paste0(round(x / 60 / 60, 1), "h")) +
labs(x = "depature", y = NULL,
title = "Prices and number of changes for different connections") +
theme_minimal()
With more data, this gets a little more interesting.
march <- bahn_search(
from = wi$id[1],
to = adam$id[1],
start = "2024-03-01T00:00:00",
end = "2024-04-01T00:00:00"
)Let’s see which days would be especially cheap:
march |>
mutate(date = as.Date(start)) |>
group_by(date) |>
slice_min(price, n = 1, with_ties = FALSE) |>
ggplot(aes(x = date, y = price)) +
geom_col() +
labs(x = NULL, y = NULL,
title = "Cheapest price per day") +
scale_y_continuous(labels = function(x) paste0(x, "€")) +
theme_minimal()
So I could get a train on any day in March for the price of 32.90€. This is all nice, but let’s only take into account connections I would actually consider:
march |>
filter(changes <= 2,
hour(start) > 7) |>
mutate(date = as.Date(start),
weekday = wday(start, label = TRUE)) |>
group_by(date) |>
slice_min(price, n = 1, with_ties = FALSE) |>
ggplot(aes(x = date, y = price, label = weekday)) +
geom_col() +
geom_text(hjust = 0, angle = 90) +
labs(x = NULL, y = NULL,
title = "Cheapest price per day with <= 2 changes and after 7am") +
scale_y_continuous(labels = function(x) paste0(x, "€")) +
theme_minimal()
It also looks like historic searches are possible.
historic <- bahn_search(
from = wi$id[1],
to = adam$id[1],
start = "2024-01-22T05:00:00",
end = "2024-01-22T19:00:00",
parse = FALSE
)I do not parse the results here to be able to explore the data a bit more (parsing only extracts the information that I found interesting on first glance). However, the results contain a message that the connection is in the past and information about price and demand seem absent.
historic[[1]][["verbindungen"]][[1]][["meldungenAsObject"]][[1]][["nachrichtLang"]]
#> [1] "Die gewählte Verbindung liegt in der Vergangenheit"