geocoding nodes of graph dont find anything

I try to georeferenz the nodes of a network. So first I extract the nodes from the network like:

nodes_index <- rails_network %>%  activate(nodes) %>% as_tibble() %>% st_as_sf() %>% mutate(long = st_coordinates(.)[,1],
                                                                                            lat = st_coordinates(.)[,2])   %>%
  st_drop_geometry()

Therefor I get a df like:

str(dput(nodes_index[1:10,1:3]))
structure(list(ID = 1:10, long = c(1233616.92623604, 1223433.99025042, 
1378366.25773239, 1401157.10267164, 1479266.77880306, 1528588.72290147, 
1509447.42453216, 1499351.98566691, 1454285.44484453, 756209.126081893
), lat = c(6350711.55217875, 6355001.32493512, 6682635.84497815, 
6684119.9464045, 6676208.51447798, 6628470.59620128, 6654633.46946046, 
6891626.20630991, 6871266.57873021, 6660285.54473999)), row.names = c(NA, 
-10L), class = c("tbl_df", "tbl", "data.frame"))
tibble [10 × 3] (S3: tbl_df/tbl/data.frame)
 $ ID  : int [1:10] 1 2 3 4 5 6 7 8 9 10
 $ long: num [1:10] 1233617 1223434 1378366 1401157 1479267 ...
 $ lat : num [1:10] 6350712 6355001 6682636 6684120 6676209 ...

and I try to geocode those by the library(revgeo) (I also tried tidygeocoder)

nodes_index1 <-    revgeo(latitude =  nodes_index$lat, longitude =  nodes_index$long, output = "frame")

But however, both ways will not find anything, eventhough confirming with library(mapview), that all nodes are where they should be.

Reverse geocoding methods generally expect geographic coordinates, but in your case the coordinate reference system (CRS) of rails_network seems to be projected -- node coordinate values are well outside expected ranges (-90 ... 90 / -180 ... 180)

To fix this, you'd need to add a transform step, it looks OK in mapview as it handles transformation for you.

Here's an example using roxel dataset:

library(sf)
#> Linking to GEOS 3.12.1, GDAL 3.8.4, PROJ 9.3.1; sf_use_s2() is TRUE
library(sfnetworks)
library(tidygeocoder)
library(dplyr)
library(tidyr)

# example dataset from sfnetworks, transformed from WGS84 to UTM Z32
roxel_sfn <- 
  roxel |> 
  st_transform(25832) |> 
  as_sfnetwork()

# nodes in projected crs (UTM, check actual point values):
roxel_sfn |> 
  activate(nodes) |> 
  st_as_sf() |> 
  print(n = 3)
#> Simple feature collection with 701 features and 0 fields
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: 398470.4 ymin: 5755557 xmax: 400124.7 ymax: 5757747
#> Projected CRS: ETRS89 / UTM zone 32N
#> # A tibble: 701 × 1
#>             geometry
#>          <POINT [m]>
#> 1 (399242.2 5757111)
#> 2 (399224.7 5757134)
#> 3 (399151.3 5756964)
#> # ℹ 698 more rows

plot(roxel_sfn, axes = TRUE)

# tranform from UTM to geogrpahic coordinates (WGS84);
# extract coordinate values
roxel_coords_wgs84 <-
  roxel_sfn |> 
  activate(nodes) |> 
  st_as_sf() |> 
  st_transform("WGS84") |> 
  mutate(coord = st_coordinates(geometry) |> as_tibble()) |> 
  unnest(coord)

roxel_coords_wgs84 |> print(n = 3)
#> Simple feature collection with 701 features and 2 fields
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: 7.522622 ymin: 51.94151 xmax: 7.546705 ymax: 51.9612
#> Geodetic CRS:  WGS 84
#> # A tibble: 701 × 3
#>              geometry     X     Y
#>           <POINT [°]> <dbl> <dbl>
#> 1 (7.533722 51.95556)  7.53  52.0
#> 2 (7.533461 51.95576)  7.53  52.0
#> 3 (7.532442 51.95422)  7.53  52.0
#> # ℹ 698 more rows

# look up addresses for first 3 records
reverse_geocode(roxel_coords_wgs84[1:3,], lat = Y, long = X)
#> Passing 3 coordinates to the Nominatim single coordinate geocoder
#> Query completed in: 3 seconds
#> # A tibble: 3 × 4
#>              geometry     X     Y address                                       
#>           <POINT [°]> <dbl> <dbl> <chr>                                         
#> 1 (7.533722 51.95556)  7.53  52.0 9, Havixbecker Straße, Roxel, Münster-West, M…
#> 2 (7.533461 51.95576)  7.53  52.0 22, Havixbecker Straße, Roxel, Münster-West, …
#> 3 (7.532442 51.95422)  7.53  52.0 Annette-von-Droste-Hülshoff-Straße, Roxel, Mü…

^{Created on 2024-07-30 with reprex v2.1.0}