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Read a GeoPackage file

Source: R/read_geopackage.R
read_geopackage.Rd

Reads an entire, or a subset of a GeoPackage vector file from disk either as a table (data.table), as a directed graph object (igraph), a spatial dataframe (sf) or a SpatVect object (terra).

Usage

read_geopackage(
  gpkg,
  import_as = "data.table",
  layer_name = NULL,
  subc_id = NULL,
  name = "stream"
)

Arguments

gpkg

character. Full path of the GeoPackage file.

import_as

character. "data.table", "graph", "sf", or "SpatVect". "data.table" imports data as a data.table. "graph" imports the layer as a directed graph (igraph object). This option is only possible for a network layer (e.g. the stream network) and it needs to contain the attributes "stream" and "next_stream". "sf" imports the layer as a spatial data frame (sf object). "SpatVect" imports the layer as a SpatVector (terra object). Default is "data.table".

layer_name

character. Name of the specific data layer to import from the GeoPackage. A specific data layer only needs to be defined if the GeoPackage contains multiple layers. To see the available layers the function st_layers() from the R package 'sf' can be used. Optional. Default is NULL.

subc_id

numeric. Vector of the sub-catchment (or stream segment) IDs in the form of (c(ID1, ID2, ...) for which the spatial objects or attributes of the GeoPackage should be imported. Optional. Default is NULL.

name

character. The attribute table column name of the stream segment ("stream"), sub-catchment ("ID"), basin ("ID") or outlet ("ID") column which is used for subsetting the GeoPackage prior importing. Optional. Default is "stream".

Author

Sami Domisch, Marlene Schürz

Examples

# Download test data into the temporary R folder
# or define a different directory
my_directory <- tempdir()
download_test_data(my_directory)


# Read the stream network as a graph
my_graph <- read_geopackage(gpkg = paste0(my_directory,
                                          "/hydrography90m_test_data",
                                          "/order_vect_59.gpkg"),
                                          import_as = "graph")

# Read the stream network as a data.table
my_dt <- read_geopackage(gpkg = paste0(my_directory,
                                       "/hydrography90m_test_data",
                                       "/order_vect_59.gpkg"))

# Read the stream network as a data.table for specific IDs
my_dt <- read_geopackage(gpkg = paste0(my_directory,
                                       "/hydrography90m_test_data",
                                       "/order_vect_59.gpkg"),
                                       subc_id = c(513833203, 513833594))

# Read the sub-catchments as a SF-object
my_sf <- read_geopackage(gpkg = paste0(my_directory,
                                       "/hydrography90m_test_data",
                                       "/sub_catchment_59.gpkg"),
                                       import_as = "sf",
                                       layer_name = "sub_catchment")

# Read a subset of sub-catchments as a SF-object
my_sf <- read_geopackage(gpkg = paste0(my_directory,
                                       "/hydrography90m_test_data",
                                       "/sub_catchment_59.gpkg"),
                                       import_as = "sf",
                                       subc_id = c(513833203, 513833594),
                                       name = "ID")

# Read the basin as SpatVect object
my_sv <- read_geopackage(gpkg = paste0(my_directory,
                                       "/hydrography90m_test_data",
                                       "/basin_59.gpkg"),
                                       import_as = "SpatVect")