在ggplot2中设置或修改标题

画一个没有标题的图, R代码如下:

stopifnot(require(ggplot2))                                

bp = ggplot(PlantGrowth, aes(x=group, y=weight)) + geom_boxplot(fill="grey") 

print(bp)                                                    

  

bp + opts(title="Plant growth")

# If the title is long, it can be split into multiple lines with \n

bp + opts(title="Plant growth with\ndifferent treatments")

# Reduce line spacing and use bold text

bp + opts(title="Plant growth with\ndifferent treatments") + 

opts(plot.title = theme_text(size=14, lineheight=.8, face="bold"))

写成一行如下, 同时添加xlab和ylab:

ggplot(PlantGrowth, aes(x=group, y=weight)) + geom_boxplot(fill="grey") + opts(title="Plant growth\ndifferent treatment") + xlab("Growth") + ylab("Weight")

在R命令上中通过help(opts)查看有关opts更多的帮助和示例.

Reference

1. http://wiki.stdout.org/rcookbook/Graphs/Titles (ggplot2)/