如何将字符串变量添加到带有按因子级别着色的标签的树状图中？答案

【问题标题】：How do I add string variables to a dendrogram with labels coloured by factor level?如何将字符串变量添加到带有按因子级别着色的标签的树状图中？
【发布时间】：2018-11-26 17:21:26
【问题描述】：

this question 的答案之一是对 iris 数据集子集的树状图标签进行颜色编码。我想做的是保留标签的字符串名称，以便他们会说 setosa、virginica 等以及它们的颜色。

这是代码

# install.packages("dendextend")
library(dendextend)

small_iris <- iris[c(1, 51, 101, 2, 52, 102), ]
dend <- as.dendrogram(hclust(dist(small_iris[,-5])))
# Like: 
# dend <- small_iris[,-5] %>% dist %>% hclust %>% as.dendrogram

# By default, the dend has no colors to the labels
labels_colors(dend)
par(mfrow = c(1,2))
plot(dend, main = "Original dend")

# let's add some color:
colors_to_use <- as.numeric(small_iris[,5])
colors_to_use
# But sort them based on their order in dend:
colors_to_use <- colors_to_use[order.dendrogram(dend)]
colors_to_use
# Now we can use them
labels_colors(dend) <- colors_to_use
# Now each state has a color
labels_colors(dend) 
plot(dend, main = "A color for every Species")

【问题讨论】：

标签： r cluster-analysis dendrogram dendextend

【解决方案1】：

您需要在绘图前更新标签。例如使用labels(dend) <- small_iris[,5][order.dendrogram(dend)]

完整代码和输出：

# install.packages("dendextend")
library(dendextend)

small_iris <- iris[c(1, 51, 101, 2, 52, 102), ]
dend <- as.dendrogram(hclust(dist(small_iris[,-5])))
# Like: 
# dend <- small_iris[,-5] %>% dist %>% hclust %>% as.dendrogram

# By default, the dend has no colors to the labels
labels_colors(dend)
par(mfrow = c(1,2))
plot(dend, main = "Original dend")

# let's add some color:
colors_to_use <- as.numeric(small_iris[,5])
colors_to_use
# But sort them based on their order in dend:
colors_to_use <- colors_to_use[order.dendrogram(dend)]
colors_to_use
# Now we can use them
labels_colors(dend) <- colors_to_use
# Now each state has a color
labels_colors(dend) 

### UPDATE <--------------------------------
labels(dend) <- small_iris[,5][order.dendrogram(dend)]


plot(dend, main = "A color for every Species")

【讨论】：