制作绘制绘图并保存的功能

Question

我有以下数据集.

structure(list(Rf = c(60.105, 62.205, 64.305, 64.305, 66.405, 
66.405), Es = c(0, -0.07, -0.36, -0.47, -0.39, -1.54), H = c(32.3, 
-6.9, -5.59, -14.4, -6.5, -21), S = c(267, 136, 151, 114, 143, 
90.4), G = c(-46.8, -47.3, -50.7, -48.5, -49, -47.8)), .Names = c("Rf", 
"Es", "H", "S", "G"), class = "data.frame", row.names = c("Me", 
"Et", "Pr", "iPr", "Bu", "tBu"))

我需要绘制Rf与H,S和G的关系,对于Es列也是如此.共有六个地块.

要绘制单个图,我使用以下函数:

ggplot(data=df, aes(x=Rf, y=H, label=row.names(df))) + 
  geom_point(size=4) +
  geom_text(vjust=2) + 
  ylab(expression(list(Delta*H^o,~kJ/mol))) + 
  xlab("Molecular refraction") + 
  ylim((min(df$H) - 0.2*(abs(min(df$H)))), max(df$H)) + 
  opts(axis.line = theme_segment(size=1),
       axis.text.x = theme_text(colour="black", size=15),
       axis.text.y = theme_text(colour="black", size=15),
       axis.title.x = theme_text(colour="black", size=15),
       axis.title.y = theme_text(colour="black", size=15, angle=90),
       panel.background=theme_rect(colour="white"),
       panel.grid.minor = theme_blank(), 
       panel.grid.major = theme_blank())

我想创建一个像这样的函数

f1 <- function(x.label, y.label, df, xtitle, filename) {
  g <- ggplot(data=df, aes(x=x.label, y=y.label, label=row.names(df))) + 
    geom_point(size=4) +
    geom_text(vjust=2) + 
    ylab(expression(list(Delta*y.label^o,~kJ/mol))) + 
    xlab(xtitle) + 
    ylim((min(df[,y.label]) - 0.2*(abs(min(df[,y.label])))), max(df[,y.label])) + 
    opts(axis.line = theme_segment(size=1),
         axis.text.x = theme_text(colour="black", size=15),
         axis.text.y = theme_text(colour="black", size=15),
         axis.title.x = theme_text(colour="black", size=15),
         axis.title.y = theme_text(colour="black", size=15, angle=90),
         panel.background=theme_rect(colour="white"),
         panel.grid.minor = theme_blank(), 
         panel.grid.major = theme_blank())
  ggsave(filename, g)
}

要为上面的例子调用它,比如

f1(Rf, H, df, "Molecular refraction", "D:/temp/1.jpg")

难的是如何转移和正确处理x.label和y.label,因为它们在使用aes的选项ggplot,ylab(expression())并ylim调用.Curent函数返回错误Error in eval(expr, envir, enclos) : object 'x.label' not found

回答:

以下功能正常工作.aes_string应使用insted的的aes的ggplot选项,substitute而不是expression在ylab.

f1 <- function(x.label, y.label, df, x.title, filename) {
  g <- ggplot(data=df, aes_string(x=x.label, y=y.label)) + 
    geom_point(size=4) +
    geom_text(aes(label=row.names(df)), vjust=2) + 
    ylab(substitute(list(Delta*y.label^o,~kJ/mol), list(y.label=y.label))) + 
    xlab(x.title) + 
    ylim((min(df[,y.label]) - 0.2*(abs(min(df[,y.label])))), max(df[,y.label])) + 
    opts(axis.line = theme_segment(size=1),
         axis.text.x = theme_text(colour="black", size=15),
         axis.text.y = theme_text(colour="black", size=15),
         axis.title.x = theme_text(colour="black", size=15),
         axis.title.y = theme_text(colour="black", size=15, angle=90),
         panel.background = theme_rect(colour="white"),
         panel.grid.minor = theme_blank(), 
         panel.grid.major = theme_blank())
  ggsave(filename=filename, plot=g)
}

Answer 1

如果输入x.label为字符（或字符串），即"Rf"，则可以使用aes_string映射美观：

aes_string(x = x.label, etc)

对 then进行子集化data.frame也变得很容易：

df[[x.label]]

对于您的表达式，ylab您可能需要使用parseand/or eval，但我现在无法访问 R 并且无法检查。