问题
I'm using R for the analysis of my master thesis I have the following data frame: STOF: Student to staff ratio
HEI.ID X2007 X2008 X2009 X2010 X2011 X2012
1 OP 41.8 147.6 90.3 82.9 106.8 63.0
2 MO 20.0 20.8 21.1 20.9 12.6 20.6
3 SD 21.2 32.3 25.7 23.9 25.0 40.1
4 UN 51.8 39.8 19.9 20.9 21.6 22.5
5 WS 18.0 19.9 15.3 13.6 15.7 15.2
6 BF 11.5 36.9 20.0 23.2 18.2 23.8
7 ME 34.2 30.3 28.4 30.1 31.5 25.6
8 IM 7.7 18.1 20.5 14.6 17.2 17.1
9 OM 11.4 11.2 12.2 11.1 13.4 19.2
10 DC 14.3 28.7 20.1 17.0 22.3 16.2
11 OC 28.6 44.0 24.9 27.9 34.0 30.7
Then I rank colleges using this commend
HEIrank1<-(STOF[,-c(1)])
rank1 <- apply(HEIrank1,2,rank)
> HEIrank11
HEI.ID X2007 X2008 X2009 X2010 X2011 X2012
1 OP 18.0 20 20.0 20.0 20.0 20
2 MO 14.0 9 13.0 13.5 2.0 12
3 SD 15.0 16 17.0 16.0 16.0 19
4 UN 20.0 18 8.0 13.5 14.0 13
5 WS 12.0 8 4.0 7.0 6.0 8
6 BF 6.5 17 9.5 15.0 10.0 14
7 ME 17.0 15 19.0 19.0 17.0 15
8 IM 2.0 6 12.0 8.0 8.5 10
9 OM 4.5 3 2.5 3.0 3.0 11
10 DC 11.0 14 11.0 9.0 15.0 9
11 OC 16.0 19 16.0 18.0 19.0 17
I would like to draw histogram for each HEIs (for each row)?
回答1:
If you use ggplot you won't need to do it as a loop, you can plot them all at once. Also, you need to reformat your data so that it's in long format not short format. You can use the melt function from the reshape package to do so.
library(reshape2)
new.df<-melt(HEIrank11,id.vars="HEI.ID")
names(new.df)=c("HEI.ID","Year","Rank")
substring is just getting rid of the X in each year
library(ggplot2)
ggplot(new.df, aes(x=HEI.ID,y=Rank,fill=substring(Year,2)))+
geom_histogram(stat="identity",position="dodge")
回答2:
Here's a solution in lattice:
require(lattice)
barchart(X2007+X2008+X2009+X2010+X2011+X2012 ~ HEI.ID,
data=HEIrank11,
auto.key=list(space='right')
)
来源：https://stackoverflow.com/questions/22264744/draw-histograms-per-row-over-multiple-columns-in-r