IceSat2R (version 1.0.6)

degrees_to_global_grid: Create a global grid based on degrees

Description

This function allows the user to create a degrees grid based on an input bounding box

Usage

degrees_to_global_grid(
  minx = -180,
  maxx = 180,
  maxy = 90,
  miny = -90,
  degrees = 1,
  square_geoms = TRUE,
  crs_value = 4326,
  verbose = FALSE
)

Value

a simple features (sf) object

Arguments

minx

the 'minx' parameter of the bounding box

maxx

the 'maxx' parameter of the bounding box

maxy

the 'maxy' parameter of the bounding box

miny

the 'miny' parameter of the bounding box

degrees

a numeric value specifying the degrees. It defaults to 1.0

square_geoms

a boolean. If FALSE then a hexagonal grid will be created

crs_value

a value. The coordinate reference system of the output grid. The crs must correspond to the EPSG of the input 'minx', 'maxx', 'miny' and 'maxy'. Moreover, the 'EPSG:4326' returns a degrees grid as output.

verbose

a boolean. If TRUE then information will be printed out in the console

Details

The default global input 'minx', 'maxx', 'miny' and 'maxy' correspond to a WKT of "POLYGON ((-180 -90, 180 -90, 180 90, -180 90, -180 -90))" When 'minx', 'maxx', 'miny' and 'maxy' EPSG is lat,long (or 'EPSG:4326') I expect the output grid to be in 'degrees' unit. Using an EPSG other than 'EPSG:4326' might return a different output unit (such as meters). See also the following 'Stackoverflow' thread for more information, https://stackoverflow.com/a/64903836/8302386

Based on 'Approximate Metric Equivalents' 1 degree is approximately 111 km (or 60 nautical miles), Reference: https://www.usna.edu/Users/oceano/pguth/md_help/html/approx_equivalents.htm

Examples

if (FALSE) {

require(IceSat2R)

#...........................................
# 'OpenAltimetry' allows 1x1 degree bounding
# box selection for the 'atl03' Product
#...........................................

gl_grid_1_d = degrees_to_global_grid(degrees = 1.0, verbose = TRUE)
gl_grid_1_d
# summary(gl_grid_1_d$area)

#...........................................................................
# 'OpenAltimetry' allows 5x5 degree bounding box selection for the following
# Products: 'atl06', 'atl07', 'atl08', 'atl10', 'atl12', 'atl13', 'level3a'
#...........................................................................

gl_grid_5_d = degrees_to_global_grid(degrees = 5.0, verbose = TRUE)
gl_grid_5_d

}