问题描述
背景
我一直致力于使用 ggplot
和 ggalluvial package 创建冲积图(一种桑基图),以可视化随时间变化的频率差异及其起源。
例如,我创建了一个简单的数据集,其中包含 100 名经过 COVID-19 筛查的虚构患者。 在基线时,所有患者的 COVID-19 均为阴性。假设 1 周后,再次对所有患者进行检测:现在,30 名患者呈阳性,65 名呈阴性,5 名患者的结果不确定。又过了一周,30 名阳性患者仍为阳性,10 名患者由阴性转为阳性,其余为阴性。
data <- data.frame(analysis = as.factor(rep(c("time0","time1","time2"),each = 4)),freq = rep(c(30,10,55,5),3),track = rep(1:4,response = c("neg","neg","pos","inconc","neg"))
# analysis freq track response
#1 time0 30 1 neg
#2 time0 10 2 neg
#3 time0 55 3 neg
#4 time0 5 4 neg
#5 time1 30 1 pos
#6 time1 10 2 neg
#7 time1 55 3 neg
#8 time1 5 4 inconc
#9 time2 30 1 pos
#10 time2 10 2 pos
#11 time2 55 3 neg
#12 time2 5 4 neg
目标
目标是创建一个冲积图,以可视化这些患者随时间推移的“轨迹”(即冲积物),从而可视化两周后结果的来源。类似的东西:
尝试
我设法制作了图形的主要部分:
library(tidyverse)
library(ggalluvial)
ggplot(data,aes(x = analysis,stratum = response,alluvium = track,y = freq,fill = response),col = "black") +
geom_flow(stat = "alluvium") +
geom_stratum(alpha = .5) +
scale_fill_manual(values = c("grey","green","red"))
问题
但是,我无法清楚地区分这些地层。现在,它们都彼此相邻,从而形成一个完全“填充”的矩形。
如何使用 ggalluvial
中的 R
包在冲积地块中分隔地层/冲积层?
解决方法
ggalluvial 包的作者将冲积图定义为:
你可能想做一个桑基情节,一个合理的包是:ggsankey
,使用 ggalluvial
,您可以这样做:
冲积地块的问题是你不会在地层上的“矿脉”之间分离。
library(ggplot2)
library(ggalluvial)
data$track <- factor(data$track)
ggplot(data,aes(x = analysis,y = freq,stratum = response,alluvium = track)) +
geom_flow(aes(fill = track),stat = "alluvium") +
geom_lode(aes(fill = response))+
geom_text(stat = "stratum",aes(label = response)) +
scale_fill_manual("Track",breaks = c("1","2","3","4","neg","pos","inconc" ),labels = c("1","",""),values = c("grey15","grey40","grey65","grey90","red","green","orange"))+
guides(fill = guide_legend(override.aes = list(alpha = c(`1` = 1,`2` = 1,`3` = 1,`4` = 1,neg = 0,pos = 0,inconc = 0))))+
theme_minimal()
由 reprex package (v2.0.0) 于 2021 年 4 月 18 日创建