read a vector spatial file to R

function for easily opening a ESRI shapefile (or other OGR valid vector file by simply specifying its filename

read_vect(in_file, as_sp = FALSE, ...)

Arguments

in_file	`character` Filename of ESRI shapefile to be opened
as_sp	`logical` If TRUE, the opened object is automatically converted to `sp` format. Otherwise, an `sf` object is returned. Default: FALSE
...	other arguments to be passed tosf::st_read

Value

sf or sp object (depending on as_sp setting)

Details

simple wrapper around sf::read_sf, with some checks on inputs and possibility of automatic re-casting to *sp objects

Examples


library(sprawl.data)
# open a shapefile as a `sf` object
 in_file = system.file("extdata/shapes","lc_polys.shp",
                        package = "sprawl.data")
 in_vect <- read_vect(in_file)
 in_vect
#> Simple feature collection with 13 features and 4 fields
#> geometry type:  POLYGON
#> dimension:      XY
#> bbox:           xmin: 120.1778 ymin: 15.15353 xmax: 121.3394 ymax: 16.09343
#> epsg (SRID):    4326
#> proj4string:    +proj=longlat +datum=WGS84 +no_defs
#> # A tibble: 13 x 5
#>       id lc_type   category sup_catego                                  geometry
#>    <dbl> <chr>     <chr>    <chr>                                  <POLYGON [°]>
#>  1     1 forest_1  Forest   Vegetation ((120.7302 15.784, 120.7369 15.784, 120.…
#>  2     2 forest_2  Forest   Vegetation ((120.3664 15.39973, 120.3672 15.40287, …
#>  3     3 urban_1   Other    Other      ((120.5941 15.49767, 120.5947 15.4984, 1…
#>  4     4 cropland… Cropland Vegetation ((120.6371 15.46567, 120.6403 15.47593, …
#>  5     5 cropland… Cropland Vegetation ((120.7231 15.54363, 120.7406 15.54973, …
#>  6     6 forest_3  Forest   Vegetation ((121.2256 16.00655, 121.2387 16.01331, …
#>  7     7 reiver_b… Other    Other      ((120.4208 15.33119, 120.4253 15.33324, …
#>  8     8 cropland… Cropland Vegetation ((120.7702 15.36887, 120.7725 15.37153, …
#>  9     9 urban_2_… Other    Other      ((120.5833 15.17092, 120.5999 15.17177, …
#> 10    10 sparsfor… Forest   Vegetation ((120.1958 15.17424, 120.2063 15.17437, …
#> 11    11 water     Other    Other      ((121.1377 15.85625, 121.1646 15.84538, …
#> 12    12 small_fe… Other    Other      ((120.78 15.93824, 120.7811 15.93814, 12…
#> 13    13 out_feat  Other    Other      ((120.6781 16.09343, 120.6942 16.08703, …

 plot_vect(in_file, fill_var = "category")
#> Coordinate system already present. Adding new coordinate system, which will replace the existing one.
#> Coordinate system already present. Adding new coordinate system, which will replace the existing one.

 in_vect <- reproj_vect(in_vect,
      "+proj=sinu +lon_0=0 +x_0=0 +y_0=0 +a=6371007.181 +b=6371007.181 +units=m +no_defs")
#> reproj_vect --> Reprojecting in_vect to +proj=sinu +lon_0=0 +x_0=0 +y_0=0 +a=6371007.181 +b=6371007.181 +units=m +no_defs
 plot_vect(in_vect, fill_var = "category",
           borders_layer = get_boundaries("PHL", level = 1)
           )
#> Coordinate system already present. Adding new coordinate system, which will replace the existing one.
#> get_boundaries --> Downloading data for: "PHL", Level: 1
#> Coordinate system already present. Adding new coordinate system, which will replace the existing one.

# open a shapefile as a `sp` object
 in_file = system.file("extdata/shapes","lc_polys.shp",
                        package = "sprawl.data")
 read_vect(in_file, as_sp = TRUE)
#> class       : SpatialPolygonsDataFrame 
#> features    : 13 
#> extent      : 120.1778, 121.3394, 15.15353, 16.09343  (xmin, xmax, ymin, ymax)
#> coord. ref. : +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0 
#> variables   : 4
#> names       : id,    lc_type, category, sup_catego 
#> min values  :  1, cropland_1, Cropland,      Other 
#> max values  : 13,      water,    Other, Vegetation

Arguments

Value

Details

See also

Examples

Contents