R：ggplot2：使用facet_wrap创建边距

Question

Say I am partitioning a scatter plot p by a single variable eg

p = p + facet_wrap(~ DayOfWeek, ncol = 3)

Is there a way to include a margin at the end of the graph ie a scatter plot which doesn't partition the data by DayOfWeek ?

Cheers fro any help

Answer 1

The easiest way I can think of is to append a copy of the data set to itself, with DayofWeek set to "all", as follows:

Make up data and base plot:

w <- c("Sun","Mon","Tues","Weds","Thurs","Fri","Sat")
f <- data.frame(x=runif(200),y=runif(200),
                DayofWeek=factor(sample(w,size=200,replace=TRUE),levels=w))
library(ggplot2)
p  <- ggplot(f,aes(x,y))+geom_point()

Append marginalized data set:

fx <- rbind(f,transform(f,DayofWeek="all"))

Substitute combined data and facet:

p %+% fx + facet_wrap(~DayofWeek,ncol=3)