r - 如何在 rgl (R) 中绘制带有图例的 3D

Question

This is what the sample looks like: 

             PC1        PC2        PC3         PC4 clusterNum
1     -3.0278979 -0.9414093 -2.0593369 -0.92992822          6
2     -1.5343149  2.5393680 -0.6645160 -0.42415503          1
3     -3.1827899  0.4878230 -2.1716015  0.87140142          1
4     -2.0630451 -0.6765663 -2.0103567 -1.20913031          6
5     -2.5608251  0.3093504 -1.8429190 -0.08175088          1
6     -2.3229565  2.1314606 -1.0680616  0.53312488          1
7     -1.8015610 -0.4233978 -0.7954366 -0.74790714          6
62378 -2.5379848 -1.3008801 -1.3621545  0.93952670          6
62379  0.5763662 -0.5990910 -0.2045754  0.32887753          5
62380  1.0751095 -0.9948755  0.4209824  0.89306204          5

 data <- structure(list(PC1 = c(-3.02789789907534, -1.53431493608036,-3.18278992851587, -2.06304508820853, -2.56082511958789, -2.32295654380193,-1.80156103002696, -2.53798478044841, 0.57636622461764, 1.07510945315635), PC2 = c(-0.94140934359441, 2.53936804189767, 0.487822997171811,-0.676566283079183, 0.309350374661524, 2.13146057296978, -0.423397780929157,-1.30088008176366, -0.599090979848925, -0.994875508747934), PC3 = c(-2.05933693083859,-0.664515950436883, -2.17160152842666, -2.01035669961785, -1.84291903624489,-1.06806160129806, -0.795436603544969, -1.36215450269855, -0.204575393904516,0.420982419847553), PC4 = c(-0.929928223454337, -0.424155026745399,0.871401419380821, -1.20913030836257, -0.0817508821137412, 0.533124880557676,-0.747907142699851, 0.939526696339997, 0.328877528585212, 0.893062041850707), clusterNum = c(6L, 1L, 1L, 6L, 1L, 1L, 6L, 6L, 5L, 5L)), row.names = c(1L,2L, 3L, 4L, 5L, 6L, 7L, 62378L, 62379L, 62380L), class = "data.frame") 

所以，我正在学习用 rgl 包在 R 中绘制 3d。我用这段代码来绘制我的数据。

plot3d(data$PC1, data$PC2, data$PC3, col=data$clusterNum) 这是我的输出；

我的问题是如何根据我的clusterNum专栏添加图例来可视化这个图表。

预先感谢您的任何帮助。

Answer 1

使用rgl::legend3d(). 您实际上可以使用graphics::legend()函数的所有参数，例如图例的定义x和y坐标，并为点字符提供值pch=以获取打印点，查找?pch任何其他形状。要获取legend=元素，只需获取集群变量sort的值。unique对于点颜色，使用您在图中所做的相同技巧。

library(rgl)
with(data, plot3d(PC1, PC2, PC3, col=clusterNum))  ## use `with` to get nicer labs
k <- sort(unique(data$clusterNum))
legend3d(x=.1, y=.95, legend=k, pch=18, col=k, title='Cluster', horiz=TRUE)