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Returns the minimal bounding box enclosing the input geometry

Source: R/ddbs_bbox.R
ddbs_bbox.Rd

Returns the minimal bounding box enclosing the input geometry from a sf object or a DuckDB table. Returns the result as an sf object or creates a new table in the database.

Usage

ddbs_bbox(
  x,
  by_feature = FALSE,
  conn = NULL,
  name = NULL,
  crs = NULL,
  crs_column = "crs_duckspatial",
  overwrite = FALSE,
  quiet = FALSE
)

Arguments

x

An sf spatial object. Alternatively, it can be a string with the name of a table with geometry column within the DuckDB database conn. Data is returned from this object.

by_feature

Boolean. The function defaults to FALSE, and returns a single bounding box for x. If TRUE, it return one bounding box for each feature.

conn

A connection object to a DuckDB database. If NULL, the function runs on a temporary DuckDB database.

name

A character string of length one specifying the name of the table, or a character string of length two specifying the schema and table names. If NULL (the default), the function returns the result as an sf object

crs

The coordinates reference system of the data. Specify if the data doesn't have a crs_column, and you know the CRS.

crs_column

a character string of length one specifying the column storing the CRS (created automatically by ddbs_write_vector). Set to NULL if absent.

overwrite

Boolean. whether to overwrite the existing table if it exists. Defaults to FALSE. This argument is ignored when name is NULL.

quiet

A logical value. If TRUE, suppresses any informational messages. Defaults to FALSE.

Value

an sf object or TRUE (invisibly) for table creation

Examples

## load packages
library(duckdb)
library(duckspatial)
library(sf)

## read data
argentina_sf <- st_read(system.file("spatial/argentina.geojson", package = "duckspatial"))
#> Reading layer `argentina' from data source 
#>   `/home/runner/work/_temp/Library/duckspatial/spatial/argentina.geojson' 
#>   using driver `GeoJSON'
#> Simple feature collection with 1 feature and 6 fields
#> Geometry type: POLYGON
#> Dimension:     XY
#> Bounding box:  xmin: -73.52455 ymin: -52.39755 xmax: -53.62409 ymax: -21.81793
#> Geodetic CRS:  WGS 84

# option 1: passing sf objects
ddbs_bbox(argentina_sf)
#> ✔ Query successful
#>       min_x     min_y     max_x     max_y
#> 1 -73.52455 -52.39755 -53.62409 -21.81793


## option 2: passing the names of tables in a duckdb db

# creates a duckdb write sf to it
conn <- duckspatial::ddbs_create_conn()
ddbs_write_vector(conn, argentina_sf, "argentina_tbl", overwrite = TRUE)
#> ℹ Table <argentina_tbl> dropped
#> ✔ Table argentina_tbl successfully imported

output2 <- ddbs_bbox(
    conn = conn,
    x = "argentina_tbl",
    name = "argentina_bbox"
)
#> ✔ Query successful

DBI::dbReadTable(conn, "argentina_bbox")
#>       min_x     min_y     max_x     max_y
#> 1 -73.52455 -52.39755 -53.62409 -21.81793