Convert object to coordinate reference system or check coordinate reference system
Source:R/as_crs.R
as_crs.Rdas_crs: coerce x to a CRS object and (optionally) error if a NA value is returned.
is_same_crs: do x and y have the same coordinate reference system?
Usage
as_crs(x = NULL, allow_na = TRUE, arg = caller_arg(x), call = caller_env())
is_same_crs(x, y)
is_wgs84(x)Arguments
- x
For
as_crs(), object to convert to a coordinate reference system. Foris_same_crs()andis_wgs84(), object to check. Foras_wgs84(), object to convert to EPSG:4326.- allow_na
For
as_crs(), ifTRUE, returnNA_crs_if x can't be converted to a valid coordinate reference system. IfFALSE, error instead of returning an invalid CRS.- arg
An argument name as a string. This argument will be mentioned in error messages as the input that is at the origin of a problem.
- call
The execution environment of a currently running function, e.g.
caller_env(). The function will be mentioned in error messages as the source of the error. See thecallargument ofabort()for more information.- y
For
is_same_crs(), object to compare to x.
Examples
nc <- sf::read_sf(system.file("shape/nc.shp", package = "sf"))
nc[["category"]] <- sample(c("A", "B", "C"), nrow(nc), replace = TRUE)
as_sf(nc$geometry)
#> Simple feature collection with 100 features and 0 fields
#> Geometry type: MULTIPOLYGON
#> Dimension: XY
#> Bounding box: xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965
#> Geodetic CRS: NAD27
#> # A tibble: 100 × 1
#> geometry
#> <MULTIPOLYGON [°]>
#> 1 (((-81.47276 36.23436, -81.54084 36.27251, -81.56198 36.27359, -81.63306 36.…
#> 2 (((-81.23989 36.36536, -81.24069 36.37942, -81.26284 36.40504, -81.26624 36.…
#> 3 (((-80.45634 36.24256, -80.47639 36.25473, -80.53688 36.25674, -80.54501 36.…
#> 4 (((-76.00897 36.3196, -76.01735 36.33773, -76.03288 36.33598, -76.04395 36.3…
#> 5 (((-77.21767 36.24098, -77.23461 36.2146, -77.29861 36.21153, -77.29351 36.1…
#> 6 (((-76.74506 36.23392, -76.98069 36.23024, -76.99475 36.23558, -77.13007 36.…
#> 7 (((-76.00897 36.3196, -75.95718 36.19377, -75.98134 36.16973, -76.18317 36.3…
#> 8 (((-76.56251 36.34057, -76.60424 36.31498, -76.64822 36.31532, -76.68874 36.…
#> 9 (((-78.30876 36.26004, -78.28293 36.29188, -78.32125 36.54553, -78.05167 36.…
#> 10 (((-80.02567 36.25023, -80.45301 36.25709, -80.43531 36.55104, -80.0481 36.5…
#> # ℹ 90 more rows
nc_bbox <- as_bbox(nc)
nc_bbox
#> xmin ymin xmax ymax
#> -84.32385 33.88199 -75.45698 36.58965
as_sfc(nc_bbox)
#> Geometry set for 1 feature
#> Geometry type: POLYGON
#> Dimension: XY
#> Bounding box: xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965
#> Geodetic CRS: NAD27
#> POLYGON ((-84.32385 33.88199, -75.45698 33.8819...
as_xy(nc[1,])
#> x y
#> 1 -81.49823 36.4314
as_sf_list(nc, col = "category")
#> <sf_list[3]>
#> $a
#> Simple feature collection with 33 features and 14 fields
#> Geometry type: MULTIPOLYGON
#> Dimension: XY
#> Bounding box: xmin: -83.98855 ymin: 33.94867 xmax: -75.45698 ymax: 36.58965
#> Geodetic CRS: NAD27
#> # A tibble: 33 × 15
#> AREA PERIMETER CNTY_ CNTY_ID NAME FIPS FIPSNO CRESS_ID BIR74 SID74 NWBIR74
#> <dbl> <dbl> <dbl> <dbl> <chr> <chr> <dbl> <int> <dbl> <dbl> <dbl>
#> 1 0.114 1.44 1825 1825 Ashe 37009 37009 5 1091 1 10
#> 2 0.07 2.97 1831 1831 Curr… 37053 37053 27 508 1 123
#> 3 0.124 1.43 1837 1837 Stok… 37169 37169 85 1612 1 160
#> 4 0.114 1.35 1838 1838 Casw… 37033 37033 17 1035 2 550
#> 5 0.153 1.62 1839 1839 Rock… 37157 37157 79 4449 16 1243
#> 6 0.072 1.08 1842 1842 Vance 37181 37181 91 2180 4 1179
#> 7 0.064 1.21 1892 1892 Avery 37011 37011 6 781 0 4
#> 8 0.086 1.27 1893 1893 Yadk… 37197 37197 99 1269 1 65
#> 9 0.128 1.55 1897 1897 Fran… 37069 37069 35 1399 2 736
#> 10 0.142 1.64 1913 1913 Nash 37127 37127 64 4021 8 1851
#> # ℹ 23 more rows
#> # ℹ 4 more variables: BIR79 <dbl>, SID79 <dbl>, NWBIR79 <dbl>,
#> # geometry <MULTIPOLYGON [°]>
#>
#> $b
#> Simple feature collection with 32 features and 14 fields
#> Geometry type: MULTIPOLYGON
#> Dimension: XY
#> Bounding box: xmin: -83.9547 ymin: 33.88199 xmax: -75.7637 ymax: 36.57286
#> Geodetic CRS: NAD27
#> # A tibble: 32 × 15
#> AREA PERIMETER CNTY_ CNTY_ID NAME FIPS FIPSNO CRESS_ID BIR74 SID74 NWBIR74
#> <dbl> <dbl> <dbl> <dbl> <chr> <chr> <dbl> <int> <dbl> <dbl> <dbl>
#> 1 0.061 1.23 1827 1827 Alle… 37005 37005 3 487 0 10
#> 2 0.143 1.63 1828 1828 Surry 37171 37171 86 3188 5 208
#> 3 0.097 1.67 1833 1833 Hert… 37091 37091 46 1452 7 954
#> 4 0.062 1.55 1834 1834 Camd… 37029 37029 15 286 0 115
#> 5 0.091 1.28 1835 1835 Gates 37073 37073 37 420 0 254
#> 6 0.143 1.66 1840 1840 Gran… 37077 37077 39 1671 4 930
#> 7 0.109 1.32 1841 1841 Pers… 37145 37145 73 1556 4 613
#> 8 0.199 1.98 1874 1874 Wilk… 37193 37193 97 3146 4 200
#> 9 0.081 1.29 1880 1880 Wata… 37189 37189 95 1323 1 17
#> 10 0.044 1.16 1887 1887 Chow… 37041 37041 21 751 1 368
#> # ℹ 22 more rows
#> # ℹ 4 more variables: BIR79 <dbl>, SID79 <dbl>, NWBIR79 <dbl>,
#> # geometry <MULTIPOLYGON [°]>
#>
#> $c
#> Simple feature collection with 35 features and 14 fields
#> Geometry type: MULTIPOLYGON
#> Dimension: XY
#> Bounding box: xmin: -84.32385 ymin: 34.30505 xmax: -76.11271 ymax: 36.55629
#> Geodetic CRS: NAD27
#> # A tibble: 35 × 15
#> AREA PERIMETER CNTY_ CNTY_ID NAME FIPS FIPSNO CRESS_ID BIR74 SID74 NWBIR74
#> <dbl> <dbl> <dbl> <dbl> <chr> <chr> <dbl> <int> <dbl> <dbl> <dbl>
#> 1 0.153 2.21 1832 1832 Nort… 37131 37131 66 1421 9 1066
#> 2 0.118 1.42 1836 1836 Warr… 37185 37185 93 968 4 748
#> 3 0.19 2.20 1846 1846 Hali… 37083 37083 42 3608 18 2365
#> 4 0.053 1.17 1848 1848 Pasq… 37139 37139 70 1638 3 622
#> 5 0.063 1 1881 1881 Perq… 37143 37143 72 484 1 230
#> 6 0.108 1.48 1900 1900 Fors… 37067 37067 34 11858 10 3919
#> 7 0.17 1.68 1903 1903 Guil… 37081 37081 41 16184 23 5483
#> 8 0.104 1.29 1907 1907 Oran… 37135 37135 68 3164 4 776
#> 9 0.059 1.32 1927 1927 Mitc… 37121 37121 61 671 0 1
#> 10 0.118 1.90 1937 1937 Mart… 37117 37117 59 1549 2 883
#> # ℹ 25 more rows
#> # ℹ 4 more variables: BIR79 <dbl>, SID79 <dbl>, NWBIR79 <dbl>,
#> # geometry <MULTIPOLYGON [°]>
#>