如何根据R中数据集的列名在多个绘图中添加数学表达式标题？

Question

keep.beta
  beta_0 C1   beta_1 C1     beta_2 C1 beta_0 C2 beta_1 C2    beta_2 C2 beta_0 C3  beta_1 C3    beta_2 C3
1  6.118431  0.14186598 -8.898830e-04  6.022789 0.2284664 -0.008715484  6.362422  0.1623198 -0.007603638
2  6.063539  0.13401758  5.027927e-06  5.986915 0.2469357 -0.009225261  6.150559  0.2002901 -0.007515155
3  6.193407  0.05483201  6.126576e-03  5.841100 0.3347416 -0.016506298  7.146271 -0.3979893  0.041127363
4  6.078092  0.05110730  6.354140e-03  5.562972 0.4690519 -0.027162758  8.179671 -1.0250484  0.089065099
5  6.256228 -0.09785900  1.856215e-02  5.644385 0.4701571 -0.027528102  8.394842 -1.2646359  0.106934875
  beta_0 C4   beta_1 C4    beta_2 C4
1  6.097189  0.16624813 -0.004341827
2  6.164902  0.09360776  0.002282821
3  6.211754  0.03602315  0.007230330
4  6.505551 -0.10780312  0.016602683
5  6.692843 -0.24754950  0.028275593

为了分别绘制每一列，我使用了以下循环，

loop.vector=1:ncol(keep.beta)
  #plot for betas
  for(b in loop.vector) {
    x.beta<-keep.beta[,b]
    plot(x.beta, type = "l", main=colnames(keep.beta)[b], ylab="") 
    mtext("beta plot",line=-1.5, cex=1.5, outer = TRUE)
    }

所有的标题都是 beta_0 C1 , beta_1 C1 等等。如何用数学符号 beta 替换标题中的所有 beta？

Answer 1

您需要正则表达式来提取 beta 和 Cs。然后使用 bquote 和变量 .() 来绘制它们。这类似于 expression() 但更灵活。 mtext 可以跳出循环。

op <- par(mfrow=c(2,3))
for(b in loop.vector) {
  x.beta <- keep.beta[,b]
  beta <- substr(sub("^beta_", '', names(keep.beta)[b]),1,2)
  Cn <- sub("^\S+\s+", '', names(keep.beta)[b] )
  plot(x.beta, type = "l", main=bquote(beta[.(beta)]~.(Cn)), ylab="") 
}
mtext("beta plot",line=-1.5, cex=1.5, outer = TRUE)
par(op)

数据:

keep.beta <- data.frame(1:5, 2:6, 3:7, 4:8, 5:9, 6:10)
names(keep.beta) <- c("beta_0 C1","beta_1 C1","beta_2 C1",
                      "beta_0 C2","beta_1 C2","beta_2 C2")

如何根据R中数据集的列名在多个绘图中添加数学表达式标题？

How to add the math expression title in multiple plots according to the column name of data set in R?

plot

r

title

symbolic-math