使用 gridExtra (ggplot) 的奇怪行为

Question

我正在尝试使用 gridExtra 包将三个地块堆叠在一起。我已经尝试了第一个使用 here 中的 grid.arrange 的例子，它工作得很好。

但是，当我尝试使用自己的图时，我得到了每个图的轴但没有数据，所有格式都被删除了。最小工作示例：

library(ggplot2)
library(gridExtra)    

popu_H0 <- seq(10, 30, length=100)
popu_H0_norm <- dnorm(popu_H0, mean = 20, sd = 4)

popu_H0_df <- as.data.frame(cbind(popu_H0, popu_H0_norm))
plot_H0 <- ggplot(popu_H0_df, aes(x=popu_H0, y=popu_H0_norm))
plot_H0 + 
  geom_line() +
  theme(
    text = element_text(size=20), 
    axis.title.x = element_text(vjust=0.1),
    axis.text.x = element_text(size = rel(1.8)),
    legend.position = "none",
    axis.title.y = element_blank(),
    axis.text.y = element_blank(),
    axis.ticks.y = element_blank(),
    axis.line.y = element_blank()
  ) +
  xlab("New label") +
  annotate("text", x = 20, y = 0.05, label = "Some annotation", size = 10) 

grid.arrange(plot_H0, plot_H0, plot_H0, ncol = 1, nrow = 3)

ggplot 产生预期的输出，但 grid.arrange 产生 this.

Answer 1

您忘记替换绘图对象。

library(ggplot2)
library(gridExtra)
popu_H0 <- seq(10, 30, length=100)
popu_H0_norm <- dnorm(popu_H0, mean = 20, sd = 4)

popu_H0_df <- as.data.frame(cbind(popu_H0, popu_H0_norm))
plot_H0 <- ggplot(popu_H0_df, aes(x=popu_H0, y=popu_H0_norm))
plot_H0 <- plot_H0 +   # Here you need `<-` to update the plot 
  geom_line() +
  theme(
    text = element_text(size=20), 
    axis.title.x = element_text(vjust=0.1),
    axis.text.x = element_text(size = rel(1.8)),
    legend.position = "none",
    axis.title.y = element_blank(),
    axis.text.y = element_blank(),
    axis.ticks.y = element_blank(),
    axis.line.y = element_blank()
  ) +
  xlab("New label") +
  annotate("text", x = 20, y = 0.05, label = "Some annotation", size = 10) 

grid.arrange(plot_H0, plot_H0, plot_H0, ncol = 1, nrow = 3)

使用 gridExtra (ggplot) 的奇怪行为

Curious behaviour using gridExtra (ggplot)

r

ggplot2

gridextra