小编Chr*_*ord的帖子

我刚刚注意到terra::cellSize()生成的单元格面积估计值与 生成的值不匹配raster::area()。

首先，为什么这两种方法不能提供相同的答案？第二，哪个估计最准确？请参阅下面的示例。

library(raster)
#> Loading required package: sp
library(terra)
#> terra version 1.3.4

# make test raster with raster::raster()
a <- raster::raster(ncols = 100, nrows = 100,
            xmn = -84, xmx = -83, 
            ymn = 42, ymx = 43)

# make test raster with terra::rast()
b <- terra::rast(ncols = 100, nrows = 100, 
          xmin = -84, xmax = -83, 
          ymin = 42, ymax = 43)

# calculate cell areas (km2)
a_area <- raster::area(a) # km …