条形图中的X轴标签和扩展数据框

我的数据

df <- structure(list(variable = c("main.tmin", "main.tmin", "main.tmin", 
                        "main.tmin", "main.tmin"), 
           coef = c(-23.28653023, 22.98726658, -55.1958095, -30.08524407, 
                    36.22033036), 
           acz = c(101L, 103L, 107L, 113L, 114L)), 
          class = "data.frame", row.names = c(NA, -5L))

library(ggplot2)

ggplot(df, aes(x = acz, y = coef)) + geom_bar(stat = "identity")  

我想做两件事:

首先我想扩大 df 从101:114开始使用ACZ 没有任何值的值中包含NA。像这样的东西

final.df <- data.frame(variable = "main.tmin",
                   acz = 101:114, 
                  coef = c(-23.28653, NA, 22.98727, NA, NA, NA, -55.19581, NA, NA, NA, NA, NA, -30.08524, 36.22033))


ggplot(final.df, aes(x = acz, y = coef)) + geom_bar(stat = "identity")

然后我要显示X轴上的所有标签,在当前时刻 仅为所选少数显示。