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Convert a bounding box to a Well Known Text polygon, and a WKT to a bounding box

Source: R/wkt_bbox.R
bbox2wkt.Rd

Convert a bounding box to a Well Known Text polygon, and a WKT to a bounding box

Usage

bbox2wkt(minx = NA, miny = NA, maxx = NA, maxy = NA, bbox = NULL)

wkt2bbox(wkt)

Arguments

minx

Minimum x value, or the most western longitude

miny

Minimum y value, or the most southern latitude

maxx

Maximum x value, or the most eastern longitude

maxy

Maximum y value, or the most northern latitude

bbox

A vector of length 4, with the elements: minx, miny, maxx, maxy

wkt

A Well Known Text string

Value

bbox2wkt returns an object of class charactere, a Well Known Text string of the form 'POLYGON((minx miny, maxx miny, maxx maxy, minx maxy, minx miny))'

wkt2bbox returns a numeric vector of length 4, like c(minx, miny, maxx, maxy).

See also

Other bbox: wkt_vis()

Other bbox: wkt_vis()

Examples

# Convert a bounding box to a WKT

## Pass in a vector of length 4 with all values
bbox2wkt(bbox = c(-125.0,38.4,-121.8,40.9))
#> [1] "POLYGON((-125 38.4,-121.8 38.4,-121.8 40.9,-125 40.9,-125 38.4))"

## Or pass in each value separately
bbox2wkt(-125.0, 38.4, -121.8, 40.9)
#> [1] "POLYGON((-125 38.4,-121.8 38.4,-121.8 40.9,-125 40.9,-125 38.4))"

# Convert a WKT object to a bounding box
wkt <- "POLYGON((-125 38.4,-125 40.9,-121.8 40.9,-121.8 38.4,-125 38.4))"
wkt2bbox(wkt)
#>   xmin ymin   xmax ymax
#> 1 -125 38.4 -121.8 40.9

identical(
 bbox2wkt(-125.0, 38.4, -121.8, 40.9),
 "POLYGON((-125 38.4,-121.8 38.4,-121.8 40.9,-125 40.9,-125 38.4))"
)
#> [1] TRUE

identical(
 c(-125.0, 38.4, -121.8, 40.9),
 as.numeric(
   wkt2bbox(
     "POLYGON((-125 38.4,-125 40.9,-121.8 40.9,-121.8 38.4,-125 38.4))"
   )
 )
)
#> [1] TRUE