r - 库 (sp) makegrid 函数中的网格坐标

r - Grid Coordinates in library(sp) makegrid function

我正在根据示例在哈里斯县(德克萨斯州休斯顿)上创建栅格:。 我的代码:

library(sp)
library(rgdal)
library(raster)

us <- getData('GADM', country = 'US', level = 2)
us$NAME_2
harris = us[us$NAME_1 == "Texas" & (us$NAME_2 == "Harris"),]

该示例声明像元大小为 0.01(以地图单位表示)。

grid <- makegrid(harris, cellsize = 0.01) # cellsize in map units!
grid <- SpatialPoints(grid, proj4string = CRS(proj4string(harris)))

但是当我单独执行"grid"时:

grid

它给出 "SpatialPoints" x1 和 x2:

SpatialPoints:
        x1    x2
[1,] -95.96 29.50
[2,] -95.95 29.50
[3,] -95.94 29.50
[4,] -95.93 29.50
[5,] -95.92 29.50
[6,] -95.91 29.50
[7,] -95.90 29.50
[8,] -95.89 29.50
...
...
...

问题:这些是网格点的经度和纬度吗?

是的,因为

> proj4string(harris)
[1] "+proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0"