Quadrats
Creates quadrat polygons for sampling or analysis
quadrats(x, s = 250, n = 100, r = NULL)
x |
A sp or sf polygon object defining extent |
s |
Radius defining single or range of sizes of quadrats |
n |
Number of quadrats |
r |
A rotation factor for random rotation, default is NULL |
an sp or sf polygon object with rotated polygon
The radius (s) parameter can be a single value or a range of values, representing a randomization range of resulting quadrat sizes. The rotation (r) parameter can also be used to defined a fixed rotation or random range of quadrat rotations. You can specify each of these parameters using an explicit vector that will be sampled eg., seq(100,300,0.5)
library(sp) library(raster) library(rgeos) data(meuse) coordinates(meuse) <- ~x+y e <- gConvexHull(meuse) # Fixed size 250 and no rotation s <- quadrats(e, s = 250, n = 50) spplot(s, "ID") # Variable sizes 100-300 and rotation of 0-45 degrees s <- quadrats(e, s = c(100,300), n = 50, r = c(0,45)) spplot(s, "ID") # Variable sizes 100-300 and no rotation s <- quadrats(e, s = c(100,300), n = 50) spplot(s, "ID")
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