V1?橫坐標(biāo)，V2數(shù)量

畫圖前加這個：

$V1=factor(data$V1,levels = rev(data$V1))

即

data<-read.table("top20.txt",header = F,sep = "\t")

data$V1=factor(data$V1,levels = rev(data$V1))

ggplot(data = data)+geom_bar(aes(data$V1,data$V2,fill=data$V1),stat="identity")+labs(x="")+ylab("Gene Number")+theme_bw()+theme(axis.text.x =? ?element_blank(),legend.title = element_blank())