问题描述
我有以下数据
structure(list(date = structure(c(1L,1L,2L,3L,4L,5L,6L,7L,8L,9L,10L,10L),.Label = c("2011","2012","2013","2014","2015","2016","2017","2018","2019","2020"),class = c("ordered","factor")),station = c("41B001","41B011_41R012","41B001","41B011_41R012"),concentration = c(NA,26.7276362390038,NA,25.6793849658314,26.4231406374957,22.318982275586,22.0774877184965,21.6359649122807,56.1669215086646,21.6140621430203,56.1504197761194,19.7031357486815,51.5015359168242,17.0787333944114,36.3595993515516,11.4634841061866
),yield = c(0,99.9200913242009,99.9544626593807,99.8287671232877,6.65983606557377,99.931693989071,89.5890410958904,99.9315068493151,97.8995433789954,99.5662100456621,96.62100456621,99.6803652968037,98.3151183970856,99.9203096539162
),environ = structure(c(2L,1L),.Label = c("Urbain avec très faible influence du trafic","Urbain avec très forte influence du trafic"),class = "factor"),environ_station = structure(c(2L,.Label = c("Urbain avec très faible influence du trafic (41B011,41R012)","Urbain avec très forte influence du trafic (41B001)"),class = "factor")),row.names = c(NA,-20L),class = c("tbl_df","tbl","data.frame"))
它是用以下代码绘制的
ggplot(data,aes(x = date,y = concentration,fill = environ_station)) +
geom_col(width = 0.75,colour = ifelse(round(data$yield,0) < 85,"red","black"),size = 0.5,position = position_dodge2(preserve = "single")) + guides(fill = guide_legend(nrow = 2)) +
geom_hline(aes(yintercept = 40),linetype = 'dashed',colour = 'red',size = 1) +
labs(x = '',y = label_conc) +
theme_minimal() + theme(legend.position="bottom",legend.title = element_blank(),legend.margin=margin(l = -2,unit='line'),legend.text = element_text(size = 10),axis.text.y = element_text(size = 10),axis.title.y = element_text(size = 10),axis.text.x = element_text(size = 10),axis.title.x = element_blank(),panel.grid.major.x = element_blank()) + geom_hline(yintercept = 0)
如图
然而，截至 2016 年的柱状图的轮廓以红色绘制，而由于产量高于 85，因此预计它们为黑色。似乎第二类中缺失的柱状图（浓度 = NA）导致问题（订单混淆）。
请问您知道如何解决这个问题吗？谢谢。
解决方法
问题在于您通过 color 参数设置边框颜色。要解决您的问题，请在 aes() 内有条件地设置颜色并使用 scale_color_manual，就像我在下面的方法中所做的那样或使用 scale_color_identity。
注意：我通过 guides 删除了生成的颜色图例。
library(ggplot2)
ggplot(data,aes(x = date,y = concentration,fill = environ_station)) +
geom_col(aes(colour = ifelse(round(yield,0) < 85,"red","black")),width = 0.75,size = 0.5,position = position_dodge2(preserve = "single")) +
scale_color_manual(values = c(red = "red",black = "black")) +
guides(fill = guide_legend(nrow = 2),color = FALSE) +
geom_hline(aes(yintercept = 40),linetype = 'dashed',colour = 'red',size = 1) +
#labs(x = '',y = label_conc) +
theme_minimal() + theme(legend.position="bottom",legend.title = element_blank(),legend.margin=margin(l = -2,unit='line'),legend.text = element_text(size = 10),axis.text.y = element_text(size = 10),axis.title.y = element_text(size = 10),axis.text.x = element_text(size = 10),axis.title.x = element_blank(),panel.grid.major.x = element_blank()) + geom_hline(yintercept = 0)
#> Warning: Removed 6 rows containing missing values (geom_col).
