Augmenting the data: Route summary statistics
We have constructed a dataset that is nearly ready for visualization, route_hod. Let's add in a few more variables that will be useful as cognostics as we anticipate interactively viewing the display.
Cet exercice fait partie du cours
Visualizing Big Data with Trelliscope in R
Instructions
- For each route, calculate the total number of rides.
- For each route, calculate the difference between the mean hourly rides during the work week and the mean hourly rides during the weekend. Note that the variable
nalready is aggregated to counts per hour, so, for example, the workweek mean is calculated withmean(n[weekday == "workweek"]). - For each route, add a variable containing a URL pointing to the route on Google Maps, using the provided
make_gmap_urlfunction, providing appropriate arguments from the data.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
library(trelliscopejs)
library(ggplot2)
library(dplyr)
# Function to construct a Google maps URL with cycling directions
make_gmap_url <- function(start_lat, start_lon, end_lat, end_lon) {
paste0("https://www.google.com/maps/dir/?api=1",
"&origin=", start_lat, ",", start_lon,
"&destination=", end_lat, ",", end_lon,
"&travelmode=bicycling")
}
# Compute tot_rides, weekday_diff, and map_url
route_hod_updated <- route_hod %>% ungroup() %>%
group_by(start_station_code, end_station_code) %>%
mutate(
tot_rides = sum(___),
weekday_diff = mean(n[weekday == "workweek"]) - ___,
map_url = ___)