当调整绘图窗口大小时,我注意到了一些奇怪的行为。考虑将点与点栅格进行绘图
library(sp)
library(rgeos)
library(raster)
rst.test <- raster(nrows=300, ncols=300, xmn=-150, xmx=150, ymn=-150, ymx=150, crs="NA")
sap.krog300 <- SpatialPoints(coordinates(matrix(c(0,0), ncol = 2)))
sap.krog300 <- gBuffer(spgeom = sap.krog300, width = 100, quadsegs = 20)
shrunk <- gBuffer(spgeom = sap.krog300, width = -30)
shrunk <- rasterize(x = shrunk, y = rst.test)
shrunk.coords <- xyFromCell(object = rst.test, cell = which(shrunk[] == 1))
plot(shrunk)
points(shrunk.coords, pch = "+")
如果调整窗口大小,绘制的点与底层栅格相比会有不同的程度。如果您重新调整窗口大小并再次绘制shrunk
和shrunk.coords
,则情节变得良好。任何人都可以解释吗?