Specify the creation of lines along meridians by specifying their placement
at particular lons (longitudes) and lats (latitudes) and their extents
with xlim (extent of parallel line in longitude) and ylim (extent of meridional line in latitude).
graticule(lons, lats, nverts = NULL, xlim, ylim, proj = NULL, tiles = FALSE)longitudes for meridional lines
latitudes for parallel lines
number of discrete vertices for each segment
maximum range of parallel lines
maximum range of meridional lines
optional proj.4 string for output object
if TRUE return polygons as output
SpatialLines or SpatialPolygons object
Provide a valid PROJ.4 string to return the graticule lines in this projection. If this is not specified the graticule
lines are returned in their original longlat / WGS84.
All segments are discretized as _rhumb_lines_ at `getOption("graticule.mindist")` metres, which
defaults to `5e4`.
The arguments xlim, ylim and nverts are ignored if tiles is TRUE.
graticule()
#> geometry ID
#> 1 MULTILINESTRING((-180 -90 ...)) 1
#> 2 MULTILINESTRING((-165 -90 ...)) 2
#> 3 MULTILINESTRING((-150 -90 ...)) 3
#> 4 MULTILINESTRING((-135 -90 ...)) 4
#> 5 MULTILINESTRING((-120 -90 ...)) 5
#> 6 MULTILINESTRING((-105 -90 ...)) 6
#> 7 MULTILINESTRING((-90 -90 ...)) 7
#> 8 MULTILINESTRING((-75 -90 ...)) 8
#> 9 MULTILINESTRING((-60 -90 ...)) 9
#> 10 MULTILINESTRING((-45 -90 ...)) 10
#> 11 MULTILINESTRING((-30 -90 ...)) 11
#> 12 MULTILINESTRING((-15 -90 ...)) 12
#> 13 MULTILINESTRING((0 -90 ...)) 13
#> 14 MULTILINESTRING((15 -90 ...)) 14
#> 15 MULTILINESTRING((30 -90 ...)) 15
#> 16 MULTILINESTRING((45 -90 ...)) 16
#> 17 MULTILINESTRING((60 -90 ...)) 17
#> 18 MULTILINESTRING((75 -90 ...)) 18
#> 19 MULTILINESTRING((90 -90 ...)) 19
#> 20 MULTILINESTRING((105 -90 ...)) 20
#> 21 MULTILINESTRING((120 -90 ...)) 21
#> 22 MULTILINESTRING((135 -90 ...)) 22
#> 23 MULTILINESTRING((150 -90 ...)) 23
#> 24 MULTILINESTRING((165 -90 ...)) 24
#> 25 MULTILINESTRING((180 -90 ...)) 25
#> 26 MULTILINESTRING((-180 -90 ...)) 26
#> 27 MULTILINESTRING((-180 -80 ...)) 27
#> 28 MULTILINESTRING((-180 -70 ...)) 28
#> 29 MULTILINESTRING((-180 -60 ...)) 29
#> 30 MULTILINESTRING((-180 -50 ...)) 30
#> 31 MULTILINESTRING((-180 -40 ...)) 31
#> 32 MULTILINESTRING((-180 -30 ...)) 32
#> 33 MULTILINESTRING((-180 -20 ...)) 33
#> 34 MULTILINESTRING((-180 -10 ...)) 34
#> 35 MULTILINESTRING((-180 0 ...)) 35
#> 36 MULTILINESTRING((-180 10 ...)) 36
#> 37 MULTILINESTRING((-180 20 ...)) 37
#> 38 MULTILINESTRING((-180 30 ...)) 38
#> 39 MULTILINESTRING((-180 40 ...)) 39
#> 40 MULTILINESTRING((-180 50 ...)) 40
#> 41 MULTILINESTRING((-180 60 ...)) 41
#> 42 MULTILINESTRING((-180 70 ...)) 42
#> 43 MULTILINESTRING((-180 80 ...)) 43
#> 44 MULTILINESTRING((-180 90 ...)) 44