`st_union(by_feature = TRUE)` between polygon and point to get a line string between point and closest point on polygon

[olivroy]

Similar to this question on Stack Overflow:

https://stackoverflow.com/questions/71240972/how-can-i-draw-a-line-from-a-point-to-a-polygon-edge-and-then-get-the-lines-len

I wonder if it was possible to get a line from combining a polygon and a point geometry. #2259

library(sf)
#> Linking to GEOS 3.12.1, GDAL 3.8.4, PROJ 9.3.1; sf_use_s2() is TRUE
nc <- st_read(system.file("shape/nc.shp", package="sf"))
#> Reading layer `nc' from data source 
#>   `C:\Users\RoyO\AppData\Local\R\win-library\4.4\sf\shape\nc.shp' 
#>   using driver `ESRI Shapefile'
#> Simple feature collection with 100 features and 14 fields
#> Geometry type: MULTIPOLYGON
#> Dimension:     XY
#> Bounding box:  xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965
#> Geodetic CRS:  NAD27
nc2 <- st_centroid(nc)
#> Warning: st_centroid assumes attributes are constant over geometries

sf::st_union(
  nc,
  nc2,
  by_feature = TRUE
)
#> Error in `st_geometry<-.data.frame`(`*tmp*`, value = value): nrow(x) == length(value) n'est pas TRUE

^{Created on 2024-08-26 with reprex v2.1.1}

Session info

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I am wondering if there is a simple solution in sf, because st_distance(by_feature = TRUE) works pretty well at giving the resulting length.

[olivroy]

Does st_line_interpolate() work? #2291 (comment)

[olivroy]

I just found st_nearest_points(), I wonder if a by_feature argument could be added?

Edit: pairwise exists. also s2::s2_minimum_clearance_line_between()