R中的桑基图标签

Sankey Diagram labels in R

背景

我正在用 R 创建一个桑基图,我正在努力标记节点。

例如,我将 一个包含 10 名接受 COVID-19 筛查的假想患者的数据集。在基线时,所有患者的 COVID-19 均为阴性。比方说 1 周后,所有患者再次接受检测:现在,3 名患者呈阳性,6 名患者呈阴性,1 名患者的结果不确定。又一周后,3名阳性患者仍为阳性,1名患者由阴性转为阳性,其余均为阴性。

data <- data.frame(patient = 1:10, 
                   baseline = rep("neg", 10), 
                   test1 = c(rep("pos",3), rep("neg", 6), "inconcl"), 
                   test2 = c( rep(NA, 3), "pos", rep("neg", 6) ))

尝试

为了创建 Sankey 图,我使用 ggsankey package:

library(tidyverse)
#devtools::install_github("davidsjoberg/ggsankey")
df <- data %>%
  make_long(baseline, test1, test2)

ggplot(df, aes(x = x, next_x = next_x, node = node, next_node = next_node,
               fill = factor(node), label = node)) +
  geom_sankey() +
  geom_sankey_label(aes(fill = factor(node)), size = 3, color = "white") +
  scale_fill_manual(values = c("grey", "green", "red")) +
  theme(legend.position = "bottom", legend.title = element_blank())

问题

我想用每个节点中存在的患者数量来标记 nodes(例如,第一个节点将标记为 10,而 inconclusive节点将被标记为 1,依此类推...)。

如何在不对值进行硬编码的情况下在 R 中执行此操作?

部分解

要从数据中提取数字,我认为初始步骤应该是这样的:

data %>% count(baseline, test1, test2)
#  baseline   test1 test2 n
#1      neg inconcl   neg 1
#2      neg     neg   neg 5
#3      neg     neg   pos 1
#4      neg     pos  <NA> 3

我想如果我能够在长数据的额外列中包含适当的值df,我应该可以从美学上调用label=variable_name

试试这个:

library(ggplot2)
library(ggsankey)
library(dplyr)


# create a count data frame for each node

df_nr <- 
  df %>% 
  filter(!is.na(node)) %>% 
  group_by(x, node)%>% 
  summarise(count = n())
#> `summarise()` has grouped output by 'x'. You can override using the `.groups` argument.

# join to sankey dataframe

df <- 
  df %>% 
  left_join(df_nr)




ggplot(df, aes(x = x, next_x = next_x, node = node, next_node = next_node,
               fill = factor(node))) +
  geom_sankey() +
  geom_sankey_label(aes(label = node), size = 3, color = "white") +
  geom_sankey_text(aes(label = count), size = 3.5, vjust = -1.5, check_overlap = TRUE) +
  scale_fill_manual(values = c("grey", "green", "red")) +
  theme_minimal()+
  theme(legend.position = "bottom",
        legend.title = element_blank())

数据

data <- data.frame(patient = 1:10, 
                   baseline = rep("neg", 10), 
                   test1 = c(rep("pos",3), rep("neg", 6), "inconcl"), 
                   test2 = c( rep(NA, 3), "pos", rep("neg", 6) ))
df <- data %>%
  make_long(baseline, test1, test2)

如果您想要边界框,您可以调整计数标签的位置或将其更改为标签(不太确定这样是否有效)。不确定 geom_sankey_label 是否识别 check_overlap 以避免计数文本的多次重叠。

reprex package (v2.0.0)

于 2021-04-20 创建