如何在 facet_grid 中增加 ggplot boxplot 的内边距？

Question

我正在设置箱线图以将这些显示在 ggplot2 facet_grid 中，并且我想增加内边距。

很遗憾，我无法增加与刻面框架的距离。

如何增加蓝色箭头所示的内边距（左右）？

require(ggplot2)
dat <- rbind(data.frame(approach=1,product=1,value=seq(1,20,0.5)), 
             data.frame(approach=1,product=2,value=seq(5,15,0.3)), 
             data.frame(approach=1,product=3,value=seq(5,17,0.2)), 
             data.frame(approach=2,product=1,value=seq(1,13,0.3)), 
             data.frame(approach=2,product=2,value=seq(3,18,0.5)), 
             data.frame(approach=2,product=3,value=seq(4,25,0.7)), 
             data.frame(approach=3,product=1,value=seq(1,15,0.6)), 
             data.frame(approach=3,product=2,value=seq(3,16,0.5)), 
             data.frame(approach=3,product=3,value=seq(1,10,0.1)))

gg1 <- ggplot(dat, aes(group =product, y = value)) + 
  geom_boxplot() + 
  ylab("size (cm)")+ 
  theme(panel.spacing = unit(0.1, 'lines')) + 
  theme(plot.background = element_rect(fill ="lightgrey" )) +
  scale_fill_grey(start = 0.0, end = 1) +
  theme_bw()+ 
  xlab("") +   
  facet_grid(cols=vars(approach)) +
  theme(axis.text.x = element_text(colour="black")) + 
  theme(axis.text.y=element_text(colour="black"))+ 
  theme(panel.spacing=unit(0,"lines")) + 
  guides(fill=guide_legend(title="Products")) + 
  theme(plot.background = element_rect(fill ="lightgrey" ))

gg1

另外，它如何适用于离散量表？

require(ggplot2)
dat <- rbind(data.frame(approach=1,product=1,value=seq(1,20,0.5)), 
             data.frame(approach=1,product=2,value=seq(5,15,0.3)), 
             data.frame(approach=1,product=3,value=seq(5,17,0.2)), 
             data.frame(approach=2,product=1,value=seq(1,13,0.3)), 
             data.frame(approach=2,product=2,value=seq(3,18,0.5)), 
             data.frame(approach=2,product=3,value=seq(4,25,0.7)), 
             data.frame(approach=3,product=1,value=seq(1,15,0.6)), 
             data.frame(approach=3,product=2,value=seq(3,16,0.5)), 
             data.frame(approach=3,product=3,value=seq(1,10,0.1)))

dat$product<-as.factor(dat$product)

gg1<-ggplot(dat, aes(x =product, y = value)) +
  geom_boxplot() + 
  ylab("size (cm)")+ 
  theme(panel.spacing = unit(0.1, 'lines')) +
  theme(plot.background = element_rect(fill ="lightgrey" )) +
  scale_fill_grey(start = 0.0, end = 1) +  
  theme_bw()+ xlab("") + 
  facet_grid(cols=vars(approach)) +
  theme(axis.text.x = element_text(colour="black")) +
  theme(axis.text.y=element_text(colour="black"))+ 
  theme(panel.spacing=unit(0,"lines")) + 
  guides(fill=guide_legend(title="Products")) + 
  theme(plot.background = element_rect(fill ="lightgrey" ))

gg1

Answer 1

您正在查看的部分是由比例控制的，而不是分面或主题边距。

以下任何一种都可以。在这种情况下，它们的结果相似，因为您的 x 值范围在 (-1, 1) 附近。更一般地，查看?expand_scale 的帮助文件，了解乘法与加法扩展因子的示例

gg1 + scale_x_continuous(expand = c(0.2, 0)) # expand scales by a multiple of 20%

gg1 + scale_x_continuous(expand = c(0, 0.2)) # expand scales by an addition of 0.2