Lesson 6 - output of st_crs

[cidfreitag]

In Lesson 6, "Open and Plot Shapefiles in R", the output of command st_crs(aoi_boundary_HARV) is given as
Coordinate Reference System:
EPSG: 32618
proj4string: "+proj=utm +zone=18 +datum=WGS84 +units=m +no_defs"

I'm getting a different result from the command. Here's the result I'm getting, which is much more detailed: (R version 3.6.3 (2020-02-29)

st_crs(aoi_boundary_HARV)

Coordinate Reference System:
User input: 32618
wkt:
PROJCS["WGS 84 / UTM zone 18N",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0,
AUTHORITY["EPSG","8901"]],
UNIT["degree",0.0174532925199433,
AUTHORITY["EPSG","9122"]],
AUTHORITY["EPSG","4326"]],
PROJECTION["Transverse_Mercator"],
PARAMETER["latitude_of_origin",0],
PARAMETER["central_meridian",-75],
PARAMETER["scale_factor",0.9996],
PARAMETER["false_easting",500000],
PARAMETER["false_northing",0],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]],
AXIS["Easting",EAST],
AXIS["Northing",NORTH],
AUTHORITY["EPSG","32618"]]

My suggestion is to replace the us of st_crs(aoi_boundary_HARV) command with st_crs(32618)$proj4string which gives the results that are in the lesson.

[cidfreitag]

Better suggestion -- replace use of st_crs(aoi_boundary_HARV) with st_crs(aoi_boundary_HARV)$proj4string
Results are
"+proj=utm +zone=18 +datum=WGS84 +units=m +no_defs "

Suggested script update:
"Remembering from an earlier lesson that CRS information connects data to the Earth’s surface using a mathematical model.
We can get more information about the object’s CRS with the st_crs() function, and the proj4string method to get information on the CRS. "
st_crs(aoi_boundary_HARV)$proj4string