par(mfrow=c(1,3))
names2<-c("0.5","0.7","0.85","1","1.35","1.5")
xx2=matrix(c(8.014,8.847,6.166,8.432,6.384,6.384,94.30,36.15,17.44,34.73,9.80,9.80),nrow=2,byrow=TRUE)
colnames(xx2)<-names2
barplot((xx2),beside=TRUE,ylim=c(0,100))
names1<-c("0.5","0.7","0.85","1","1.35","1.5")
xx=matrix(c(0.620,0.592,0.594,0.590,0.572,0.546,0.629,0.588,0.605,0.594,0.590,0.561),nrow=2,byrow=TRUE)
colnames(xx)<-names1
barplot((xx),beside=TRUE,ylim=c(0,0.8))
names3<-c("0.5","0.7", "0.85", "1","1.35","1.5")
xx3=matrix(c(1.021,1.195,1.061,1.205,1.12, 1.160,  1.153,1.290,1.147,1.276,1.16,1.183),nrow=2,byrow=TRUE)
colnames(xx3)<-names3
barplot((xx3),beside=TRUE,ylim=c(0,1.5))
为什么三个图中的一些横坐标值没有了呢？大家帮忙解决一下吧，多谢啦。