ggplot2中的多条曲线具有相同的自变量

Question

我在x轴上有一系列点，每个点在y轴上有两个点。

x<-seq(8.5,10,by=0.1)
y<-c(0.9990276914, 0.9973015358, 0.9931704801, 0.9842176288, 0.9666471511, 0.9354201700, 0.8851624615, 0.8119131899, 0.7152339504, 0.5996777045, 0.4745986612, 0.3519940258, 0.2431610835, 0.1556738744, 0.0919857178, 0.0500000000, 0.0249347645, 0.0113838852, 0.0047497169, 0.0018085048, 0.0006276833)
y1<-c(9.999998e-01,9.999980e-01,9.999847e-01,9.999011e-01,9.994707e-01,9.976528e-01,9.913453e-01, 9.733730e-01, 9.313130e-01, 8.504646e-01, 7.228116e-01, 5.572501e-01,3.808638e-01,2.264990e-01, 1.155286e-01, 5.000000e-02, 1.821625e-02, 5.554031e-03, 1.410980e-03, 2.976926e-04, 5.203069e-05)

我现在想在ggplot2中创建两条曲线。这在R中以常规方式很容易实现。结果如下图所示。但是，我不确定如何在ggplot2中这样做。对于一条曲线，我可以使用

library(ggplot2)
p<-qplot(x,y,geom="line")

你能帮我概括一下吗？非常感谢任何帮助，谢谢。

Answer 1

请注意，x和y值的长度不匹配。合并您的数据并使用分组变量：

x<-seq(8.5,10, length.out = 21)
DF <- data.frame(x=rep(x, 2), y=c(y, y1), g=c(y^0, y1^0*2))

library(ggplot2)
ggplot(DF, aes(x=x, y=y, colour=factor(g), linetype=factor(g))) + 
  geom_line()

Answer 2

正如@Roland首先指出的那样，你应该确定x的长度。使用reshape2包的可能解决方案：

library(reshape2)
library(ggplot2)

x<-seq(8.5,10,length.out = 21)
y<-c(0.9990276914, 0.9973015358, 0.9931704801, 0.9842176288, 0.9666471511, 0.9354201700, 0.8851624615, 0.8119131899, 0.7152339504, 0.5996777045, 0.4745986612, 0.3519940258, 0.2431610835, 0.1556738744, 0.0919857178, 0.0500000000, 0.0249347645, 0.0113838852, 0.0047497169, 0.0018085048, 0.0006276833)
y1<-c(9.999998e-01,9.999980e-01,9.999847e-01,9.999011e-01,9.994707e-01,9.976528e-01,9.913453e-01, 9.733730e-01, 9.313130e-01, 8.504646e-01, 7.228116e-01, 5.572501e-01,3.808638e-01,2.264990e-01, 1.155286e-01, 5.000000e-02, 1.821625e-02, 5.554031e-03, 1.410980e-03, 2.976926e-04, 5.203069e-05)

df <- data.frame(x, y, y1)

df <- melt(df, id.var='x')


ggplot(df, aes(x = x, y = value, color = variable))+geom_line()

修改 更改线型和图例：

g <- ggplot(df, aes(x = x, y = value, color = variable, linetype=variable)) + geom_line()

g <- g +  scale_linetype_discrete(name="Custom legend name",
                              labels=c("Curve1", "Curve2"))

g <- g + guides(color=FALSE)

print(g)