R-ggplot2-如何绘制对称条形图并添加旋转标签？

目录

• 0.问题导入

• 1.示例数据随机生成

• 2.对称正负y空间展示双正样本

• 3.如何使得y轴的标签均为正？

• 4.如何增加垂直方向上的标注？

• 5.再优化下

• 6.总结

• 7.本篇所用到的R-packages（没有的需要用install.packages('包名'）进行安装）

• 8.参考文献

• 9.致谢

• 10.号外：技术公众号【TheWhoOPs】上线啦～～

0.问题导入

在日常条形图绘制过程中，为了突出对比两个样本并便于标注值的大小，我们需要将两个赋值均为正的样本分别在y值的正负空间进行展示与标注，如图1。图1 问题说明（Li et al., 2019)那么问题来了：1. 如何将两组正值分别在y轴的正负空间进行分别展示？2. 如何使得y轴的标签均为正？3. 如何增加垂直方向上的标注？

本篇将逐一解决以上问题

1. 示例数据随机生成

setwd('/Users/jerseyshen/Documents/JianShu_Project/20200206')

df = data.frame(
Group = rep(c('Group_A','Group_B','Group_C','Group_D'),2),
Frequency = c(runif(4,0,100),runif(4,-100,0)),
Type = rep(c('TypeA','TypeB'),each = 4)
)
df$Label = paste0(round(df$Frequency,2),"%")
head(df)
Group Frequency Type Label
1 Group_A 27.415620 TypeA 27.42%
2 Group_B 39.089917 TypeA 39.09%
3 Group_C 17.649449 TypeA 17.65%
4 Group_D 68.757908 TypeA 68.76%
5 Group_A -26.046330 TypeB -26.05%
6 Group_B -3.421074 TypeB -3.42%

2. 对称正负y空间展示双正样本

实现这一步的思路是将需要展示在y轴负空间的值赋予相反值，本篇示例数据df已将TypeB的值进行了求负处理（图2）。但是问题是我们需要展示的样本真值为正，如果我们把图2直接插入到论文中，肯定会导致读者误认为TypeB值为负的问题。因此，接下来，我们需要将y轴的轴标签进行均正处理。

p1 = ggplot()+
geom_bar(data = df,aes(x = Group,y = Frequency,fill = Type),
color = 'black',stat = 'identity',position = 'stack')+
theme_bw()+
theme(legend.position = 'bottom',
legend.direction = 'horizontal',
axis.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
axis.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'),
legend.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
legend.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'))+
ylab('Frequency (%)')

png('plot1.png',
height = 15,
width = 20,
units = 'cm',
res = 800)
print(p1)
dev.off()

图2 对称正负y空间展示双正样本

3. 如何使得y轴的标签均为正？

p2 = ggplot()+
geom_bar(data = df,aes(x = Group,y = Frequency,fill = Type),
color = 'black',stat = 'identity',position = 'stack')+
scale_y_continuous(limits = c(-100,100),breaks = c(-100,-50,0,50,100),labels = c(100,50,0,50,100))+
theme_bw()+
theme(legend.position = 'bottom',
legend.direction = 'horizontal',
axis.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
axis.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'),
legend.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
legend.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'))+
ylab('Frequency (%)')

png('plot2.png',
height = 15,
width = 20,
units = 'cm',
res = 800)
print(p2)
dev.off()

图3 如何使得y轴的标签均为正？

4. 如何增加垂直方向上的标注？

p3 = ggplot()+
geom_bar(data = df,aes(x = Group,y = Frequency,fill = Type),
color = 'black',stat = 'identity',position = 'stack')+
geom_text(data = df,aes(x = Group, y= Frequency, label = Label,color = Type),
angle = 90,size = 5,nudge_y =c(rep(20,4),rep(-20,4)))+
scale_y_continuous(limits = c(-100,100),breaks = c(-100,-50,0,50,100),labels = c(100,50,0,50,100))+
theme_bw()+
theme(legend.position = 'bottom',
legend.direction = 'horizontal',
axis.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
axis.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'),
legend.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
legend.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'))+
ylab('Frequency (%)')

png('plot3.png',
height = 15,
width = 20,
units = 'cm',
res = 800)
print(p3)
dev.off()

图4 如何增加垂直方向上的标注？

5. 再优化下

疫情期间用Lancet 色带组祈福！

p4 = ggplot()+
geom_bar(data = df,aes(x = Group,y = Frequency,fill = Type),
color = 'black',stat = 'identity',position = 'stack',width = 0.4)+
geom_text(data = df,aes(x = Group, y= Frequency, label = Label,color = Type),
angle = 90,size = 5,nudge_y =c(rep(20,4),rep(-20,4)))+
scale_y_continuous(limits = c(-100,100),breaks = c(-100,-50,0,50,100),labels = c(100,50,0,50,100))+
scale_fill_lancet()+
scale_color_lancet()+
geom_hline(aes(yintercept = 0),size = 0.2)+
theme_bw()+
theme(legend.position = 'bottom',
legend.direction = 'horizontal',
axis.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
axis.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'),
legend.text = element_text(size = 12,hjust = 0.5,face = 'bold',color = 'black'),
legend.title = element_text(size = 14,hjust = 0.5,face = 'bold',color = 'black'),
panel.grid = element_line(color = 'transparent'))+
ylab('Frequency (%)')

png('plot4.png',
height = 15,
width = 20,
units = 'cm',
res = 800)
print(p4)
dev.off()

图4 优化后的图件

6. 总结

本篇共解决了以下几个问题：1. 如何将两组正值分别在y轴的正负空间进行分别展示？2. 如何使得y轴的标签均为正？3. 如何增加垂直方向上的标注？

7. 本篇所用到的R-packages（没有的需要用install.packages('包名'）进行安装）

library(ggplot2)
library(ggsci)

8. 参考文献

Li, J., Wu, C., Wang, X., Peng, J., Dong, D., Lin, G., & Gonsamo, A. (2020). Satellite observed indicators of the maximum plant growth potential and their responses to drought over Tibetan Plateau (1982–2015). Ecological Indicators, 108, 105732.

9. 致谢

首先，感谢大家的持续关注，小编会继续努力，持续更新下去的！

大家如果觉得有帮助啊，还麻烦大家关注点赞，也可以扩散到朋友圈，多多引导朋友加入咱们这个简书技术平台, 代码共享推动科研进程, 多谢大家啦～

大家如果在使用本代码的过程有遇到问题的，可以留言评论，也可以私信我哈~~

祝大家身体健康！！

小编联系方式

10. 号外：技术公众号【TheWhoOPs】上线啦～～

为了方便大家的阅读方便，技术公众号【TheWhoOPs】已经上线啦！！欢迎大家关注及转发哈，感谢大家鼎力支持！！