R 3d图与分类颜色

Question

我在R中有4列数据,看起来像这样

x   y   z  group

该group列有分类值,因此它是一组离散值,而其它三列是连续的.

我想在R中创建一个带有x,, y和的三维图,并且z点的颜色由"group"给出.我也希望有一个这个情节的传奇.我怎样才能做到这一点？我对实际颜色没有特别的偏好.我想rainbow(length(unique(group))应该没问题.

Answer 1

以下是使用scatterplot3d并基于插图中的示例的示例

library(scatterplot3d)

# some basic dummy data
DF <- data.frame(x = runif(10),
  y = runif(10), 
  z = runif(10), 
  group = sample(letters[1:3],10, replace = TRUE))

# create the plot, you can be more adventurous with colour if you wish
s3d <- with(DF, scatterplot3d(x, y, z, color = as.numeric(group), pch = 19))

# add the legend using `xyz.convert` to locate it 
# juggle the coordinates to get something that works.
legend(s3d$xyz.convert(0.5, 0.7, 0.5), pch = 19, yjust=0,
       legend = levels(DF$group), col = seq_along(levels(DF$group)))

或者,您可以使用lattice和cloud,在这种情况下,您可以使用构造密钥key

cloud(z~x+y, data = DF, pch= 19, col.point = DF$group, 
  key = list(points = list(pch = 19, col = seq_along(levels(DF$group))), 
  text = list(levels(DF$group)), space = 'top', columns = nlevels(DF$group)))