Compare graph distance vs. geographic distance

Case Studies: Network Analysis in R

Edmund Hart

Instructor

Graph distance

farthest_vertices(trip_g_simp)

$vertices
+ 2/300 vertices, named, from 20dcfff:
[1] 336 340

$distance
[1] 5

get_diameter(trip_g_simp)

+ 4/300 vertices, named, from 20dcfff:
[1] 336 267 76  340

Geographic distance

library(geosphere)

# Get the to stations coordinates
st_to <- bike_dat %>% 
            filter(from_station_id == 336) %>% 
            sample_n(1) %>% 
            select(from_longitude, from_latitude)
# Get the from stations coordinates
st_from <- bike_dat %>% 
            filter(from_station_id == 340) %>% 
            sample_n(1) %>% 
            select(from_longitude, from_latitude)

# find the geographic distance
farthest_dist <- distm(st_from, st_to, fun = distHaversine)
farthest_dist

[1, ] 13660.66

Geographic distance

bike_dist <- function(station_1, station_2, divy_bike_df){
    st1 <- divy_bike_df %>% 
                filter(from_station_id == station_1) %>% 
                sample_n(1) %>% 
                select(from_longitude, from_latitude)
    st2 <- divy_bike_df %>%
                filter(from_station_id == station_2) %>% 
                sample_n(1) %>% 
                select(from_longitude, from_latitude)

    farthest_dist <- distm(st1, st2, fun = distHaversine)
    return(farthest_dist)
}

Let's practice!

Case Studies: Network Analysis in R