r - 更改我的 ggplot 树状图中的字体

Question

我尝试绘制一个彩色树状图以包含在我的论文中，除一件事外一切正常:更改字体。我以前画过很多树状图，改变字体从来都不是问题，但在这段代码中突然是......我可能试图在任何可能的空间写 family="serif"，但 idoes 不起作用。我的代码:

dencw3m <- as.dendrogram(aggl.clust.manhattan.ward.cw3m)

dendro.col.cw3m <- dencw3m %>%
  set("branches_k_color", k = 5, value =   c("blue", "red", "limegreen", "gold", "darkorange")) %>%
  set("branches_lwd", 0.6) %>%
  set("labels_colors", 
      value = c("darkslategray")) %>% 
  set("labels_cex", 0.5)

gg.cw3m <- as.ggdend(dendro.col.cw3m)

ggplot(gg.cw3m, theme = theme_minimal()) +
  labs(x = "Fall", y = "Homogenität", title = "Dendrogramm cw3m", family = "serif", cex = 0.4, hang = -1)

Answer 1

我不熟悉 dendextend 包，所以不确定它是否提供了一个简单的选项来通过参数设置字体系列。但是，由于最终结果是 ggplot 对象，实现所需结果的一种选择是手动设置 geom_text 的 family 参数用于添加标签的图层。

使用 ?ggdend 中的默认示例:

library(dendextend)
library(ggplot2)

dend <- iris[1:30, -5] %>%
  dist() %>%
  hclust() %>%
  as.dendrogram() %>%
  set("branches_k_color", k = 5, value =   c("blue", "red", "limegreen", "gold", "darkorange")) %>%
  set("branches_lwd", 0.6) %>%
  set("labels_colors", 
      value = c("darkslategray")) %>% 
  set("labels_cex", 0.5)

ggd1 <- as.ggdend(dend, theme = theme_minimal())

p <- ggplot(ggd1)

查看 p 的层，我们看到 geom_text 是第三层:

p$layers
#> [[1]]
#> mapping: xend = ~xend, yend = ~yend, colour = ~col, linetype = ~lty, size = ~lwd, x = ~x, y = ~y 
#> geom_segment: arrow = NULL, arrow.fill = NULL, lineend = square, linejoin = round, na.rm = TRUE
#> stat_identity: na.rm = TRUE
#> position_identity 
#> 
#> [[2]]
#> mapping: colour = ~col, shape = ~pch, size = ~cex, x = ~x, y = ~y 
#> geom_point: na.rm = TRUE
#> stat_identity: na.rm = TRUE
#> position_identity 
#> 
#> [[3]]
#> mapping: label = ~label, colour = ~col, size = ~cex, x = ~x, y = ~y 
#> geom_text: parse = FALSE, check_overlap = FALSE, na.rm = FALSE
#> stat_identity: na.rm = FALSE
#> position_identity

因此，要切换字体系列，我们可以像这样设置该层的 aes_params 的 family 参数:

p$layers[[3]]$aes_params$family <- "serif"
p