情節連接情節的外點的直線

Question

我想繪製連接情節的外點

plot(rnorm(1000), rnorm(1000), xlim=c(-5,5),ylim=c(-5,5)) 

因而「袋」的情節的所有點線

Answer 1

這裏使用的函數是chull。第4行在那裏關閉該圈。有關更多示例，請參閱here。

x <- data.frame(x = rnorm(100), y = rnorm(100)) 
plot(x) 
chx <- chull(x) 
chx <- rbind(x = x[chx, ], x[chx[1], ]) 
lines(chx) 

Answer 2

a <- rnorm(1000) 
b <- rnorm(1000) 


Plot_ConvexHull<-function(xcoord, ycoord, lcolor){ 
hpts <- chull(x = xcoord, y = ycoord) 
hpts <- c(hpts, hpts[1]) 
lines(xcoord[hpts], ycoord[hpts], col = lcolor) 
} 

(xrange <- range(c(a))) 
(yrange <- range(c(b))) 

par(tck = 0.02, mgp = c(1.7, 0.3, 0)) 
plot(a, b, type = "p", pch = 1, col = "black", xlim = c(xrange), ylim = c(yrange)) 
Plot_ConvexHull(xcoord = a, ycoord = b, lcolor = "black")