Create a simple feature POINT geometry column

This function creates a simple feature POINT geometry column from x and y columns in a data frame. The resulting object is a sf geometry set that can be used as an additional spatial column in an sf data frame, in addition to the primary geometry column.

Usage

sf_point_col(x, y, crs = sf::NA_crs_)

Arguments

x

A vector of x coordinates (e.g., longitude or easting)

y

A vector of y coordinates (e.g., latitude or northing)

crs

An optional coordinate reference system (CRS) to assign to the geometry. This can be an EPSG code (numeric) or a proj4 string (character). If not set (default), no CRS is assigned.

Value

A sf geometry set of POINT geometries

Examples

sf_point_col(
  x = show_meta(example_tt)$nest_lon,
  y = show_meta(example_tt)$nest_lat,
  crs = 4326
)
#> Geometry set for 3 features 
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: -2.44 ymin: -1.76 xmax: 1.37 ymax: 0.43
#> Geodetic CRS:  WGS 84
#> POINT (1.37 0.06)
#> POINT (-2.44 -1.76)
#> POINT (-0.78 0.43)

# assign to a column in the meta with mutate
library(dplyr)
show_meta(example_tt) %>%
  mutate(nest_coord = sf_point_col(
    x = show_meta(example_tt)$nest_lon,
    y = show_meta(example_tt)$nest_lat,
    crs = 4326
  ))
#>   track_id    sex nest_lon nest_lat          nest_coord
#> 1        a   male     1.37     0.06   POINT (1.37 0.06)
#> 2        b   male    -2.44    -1.76 POINT (-2.44 -1.76)
#> 3        c female    -0.78     0.43  POINT (-0.78 0.43)