利用ggplot2绘制点图

目的：使用ggplot2绘制二维点图。
输入文件格式：

Type    a   b   c
botrytis    1.061400134 1.864434621 1.756580352
capitata    1.071468013 2.105041727 1.964633289
botrytis    1.098937678 2.757260101 2.509023173
botrytis    1.142003064 2.28265522  1.99881707
italica 1.155204592 4.618688189 3.998156014
capitata    1.249593966 2.43867596  1.951574692

脚本如下：

library(ggplot2)


mytheme2 <- theme_bw() + theme(legend.title=element_blank(), panel.grid.major = element_blank(), panel.grid.minor = element_blank(),

                               axis.title.x = element_text(size=8),
                               axis.title.y = element_text(size=8,angle=90),
                               #axis.title.y = element_text(size=8,angle=90),
                               axis.text.x=element_text(size=9,angle=0),
                               axis.text.y = element_text(size=7),  ##- biao qian
                               #axis.ticks.y = element_blank(), ##- ke du xian 
                               legend.position="top",
                               legend.key.size = unit(0.4,'cm'),
                               legend.text = element_text(size=6,angle=0),
                               strip.text = element_text(size=8)

                              )

argv<-commandArgs(TRUE)

data1 <- read.table(argv[1], header = T, sep="\t")

#data1$Chr <- factor(data1$Chr, levels=c("A01", "A02", "A03", "A04", "A05", "A06", "A07", "A08", "A09", "A10"))
#chrColor <- c("#FFFFFF", "#9933FF", "#FF33FF", "#FF3399", "#FF3333", "#FF9933", "#99FF33", "#33FF99", "#3399FF", "#B8B800")

p2 <- ggplot(data1, aes(x=a, y=b, colour=Type, fill=Type, group=Type)) +
      geom_point(size=3, shape=16, alpha=0.8) +
      #facet_grid(Sam1vsSam2 ~ Chr,as.table=TRUE, scales="free_x", space="free_x")  +
      #geom_vline(data=subset(data1, Chr=="A02"), aes(xintercept=18122666/1000000), colour="#990000", linetype="dashed")  +
      #geom_vline(data=subset(data1, Chr=="A10"), aes(xintercept=1616321/1000000), colour="#990000", linetype="dashed")  +
      ylab("D4/D1") + xlab("D3/D1") +  mytheme2

ggsave(filename=argv[2],plot=p2,height=4,width=4)

结果图：

image.png