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Create a rectangular polygon from bounding coordinates

Source: R/ddbs_extent_funs.R
ddbs_make_envelope.Rd

Creates a rectangular POLYGON geometry from four bounding coordinates.

Usage

ddbs_make_envelope(
  xmin,
  ymin,
  xmax,
  ymax,
  crs = "EPSG:4326",
  name = NULL,
  conn = NULL,
  mode = NULL,
  overwrite = FALSE,
  quiet = FALSE
)

Arguments

xmin

A numeric value for the minimum X (longitude) coordinate.

ymin

A numeric value for the minimum Y (latitude) coordinate.

xmax

A numeric value for the maximum X (longitude) coordinate.

ymax

A numeric value for the maximum Y (latitude) coordinate.

crs

A character string specifying the coordinate reference system of the output geometry. Default is "EPSG:4326".

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

conn

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

mode

Character. Controls the return type. Options:

  • "duckspatial" (default): Lazy spatial data frame backed by dbplyr/DuckDB

  • "sf": Eagerly collected sf object (uses memory)

Can be set globally via ddbs_options(mode = "...") or per-function via this argument. Per-function overrides global setting.

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

Depends on the mode argument (or global preference set by ddbs_options):

  • duckspatial (default): A duckspatial_df (lazy spatial data frame) backed by dbplyr/DuckDB.

  • sf: An eagerly collected object in R memory, that will return the same data type as the sf equivalent (e.g. sf or units vector).

When name is provided, the result is also written as a table or view in DuckDB and the function returns TRUE (invisibly).

Examples

if (FALSE) { # \dontrun{
## load package
library(duckspatial)

## without storing in duckdb
finland_bbox_ddbs <- ddbs_make_envelope(
  xmin = 19.1, ymin = 59.7,
  xmax = 31.6, ymax = 70.1
)
} # }