Create a bounding box for spatial queries

Wraps four corner coordinates into an sl_bbox vector used by sl_search() and sl_read(). The main value is up-front validation: arguments are checked for correct ordering (xmin < xmax, ymin < ymax) and for coordinates falling within WGS84 bounds (latitude in [-90, 90], longitude in [-180, 180]), so mistakes surface here rather than as a silent empty search or a failed HTTP request.

Usage

sl_bbox(xmin, ymin, xmax, ymax)

Arguments

xmin

Minimum longitude (western boundary).

ymin

Minimum latitude (southern boundary).

xmax

Maximum longitude (eastern boundary).

ymax

Maximum latitude (northern boundary).

Value

A named double vector of class sl_bbox.

Examples

# Construct a bounding box over a Pacific Northwest forest site.
sl_bbox(-124.04, 41.39, -124.01, 41.42)
#> <sl_bbox>: (-124.0400, 41.3900) - (-124.0100, 41.4200)

# Validation catches common mistakes before they reach the search
# or reader. Wrap in try() so the example chunk keeps running.
try(sl_bbox(-124.01, 41.39, -124.04, 41.42))  # xmin >= xmax
#> Error in sl_bbox(-124.01, 41.39, -124.04, 41.42) : 
#>   `xmin` must be less than `xmax`.
try(sl_bbox(0, -100, 1, 1))                   # latitude out of range
#> Error in sl_bbox(0, -100, 1, 1) : 
#>   Latitude values must be between -90 and 90.