堆叠的条形图标签在删除因子后发生变化（ggplot2）

Question

我在下面的position_stack(reverse = TRUE)和geom_bar中都使用geom_text，以使文本与正确的组对齐。当包括所有因素时，它工作正常，但是，当至少去除了一个因素时，标签会更改位置（并且图形的宽度也会改变吗？）

library(ggplot2)
library(dplyr)
library(scales)

dat <- data.frame(
  group = factor(
    c("A", "B", "C"),
    levels = c("A", "B", "C"),
    ordered = TRUE
  ),
  value = c(0.7, 0.2, 0.1))

dat %>%
  ggplot(aes(x = 1, y = value, fill = group)) +
  geom_bar(
    stat = "identity",
    position = position_stack(reverse = TRUE),
    width = 0.6,
    show.legend = FALSE
  ) +
  theme_void() +
  geom_label(
    aes(
      x = 0.65,
      y = value,
      label = percent(value, 1),
      fontface = "bold"
    ),
    position = position_stack(reverse = TRUE),
    vjust = 1.5,
    size = 5,
    colour = "white",
    show.legend = FALSE
  )

dat %>%
  filter(group %in% c("B", "C")) %>%
  ggplot(aes(x = 1, y = value, fill = group)) +
  geom_bar(
    stat = "identity",
    position = position_stack(reverse = TRUE),
    width = 0.6,
    show.legend = FALSE
  ) +
  theme_void() +
  geom_label(
    aes(
      x = 0.65,
      y = value,
      label = percent(value, 1),
      fontface = "bold"
    ),
    position = position_stack(reverse = TRUE),
    vjust = 1.5,
    size = 5,
    colour = "white",
    show.legend = FALSE
  )

sessionInfo()
#> R version 3.6.1 (2019-07-05)
#> Platform: x86_64-w64-mingw32/x64 (64-bit)
#> Running under: Windows 10 x64 (build 18362)
#> 
#> Matrix products: default
#> 
#> locale:
#> [1] LC_COLLATE=English_New Zealand.1252  LC_CTYPE=English_New Zealand.1252   
#> [3] LC_MONETARY=English_New Zealand.1252 LC_NUMERIC=C                        
#> [5] LC_TIME=English_New Zealand.1252    
#> 
#> attached base packages:
#> [1] stats     graphics  grDevices utils     datasets  methods   base     
#> 
#> other attached packages:
#> [1] scales_1.1.0  dplyr_0.8.5   ggplot2_3.3.0
#> 
#> loaded via a namespace (and not attached):
#>  [1] Rcpp_1.0.4.6      knitr_1.28        magrittr_1.5      tidyselect_1.0.0 
#>  [5] munsell_0.5.0     viridisLite_0.3.0 colorspace_1.4-1  R6_2.4.1         
#>  [9] rlang_0.4.5       stringr_1.4.0     highr_0.8         tools_3.6.1      
#> [13] grid_3.6.1        gtable_0.3.0      xfun_0.13         withr_2.2.0      
#> [17] htmltools_0.4.0   ellipsis_0.3.0    assertthat_0.2.1  yaml_2.2.1       
#> [21] digest_0.6.25     tibble_3.0.1      lifecycle_0.2.0   crayon_1.3.4     
#> [25] farver_2.0.3      purrr_0.3.4       vctrs_0.2.4       glue_1.4.0       
#> [29] evaluate_0.14     rmarkdown_2.1     labeling_0.3      stringi_1.4.6    
#> [33] compiler_3.6.1    pillar_1.4.3      pkgconfig_2.0.3

^{由reprex package（v0.3.0）在2020-04-30创建}

Answer 1

这实际上与您的因子下降无关。 ggplot2不允许您使用位置堆栈和微移（这是您理想的方式）。您可以绘制图形，然后进行调整并重新绘制。

library(ggplot2)
library(dplyr)
library(scales)
library(grid)

dat <- data.frame(
  group = factor(
    c("A", "B", "C"),
    levels = c("A", "B", "C"),
    ordered = TRUE
  ),
  value = c(0.7, 0.2, 0.1))


p1 <- dat %>%
  ggplot(aes(x = 1, y = value, fill = reorder(group, value))) +
  geom_bar(
    stat = "identity",
    position = "stack",
    show.legend = FALSE
  ) +
  theme_void() +
  geom_label(
    aes(
      y = value,
      label = percent(value, 1),
      fontface = "bold"
    ),
    position = position_stack(vjust = .5),
    size = 5,
    colour = "white",
    show.legend = FALSE
  )+
  xlim(c(.5,1.5))

p1 <- ggplot_build(p1)

#change label position
p1$data[[2]]$x <- p1$data[[2]]$x - .5
#rebuild graph
grid.draw(ggplot_gtable(p1))
dev.off()

p2 <- dat %>%
  filter(group %in% c("B", "C")) %>%
  ggplot(aes(x = 1, y = value, fill = reorder(group, value))) +
  geom_bar(
    stat = "identity",
    position = "stack",
    show.legend = FALSE
  ) +
  theme_void() +
  geom_label(
    aes(
      y = value,
      label = percent(value, 1),
      fontface = "bold"
    ),
    position = position_stack(vjust = .5),
    size = 5,
    colour = "white",
    show.legend = FALSE
  )+
  xlim(c(.5,1.5))


p2 <- ggplot_build(p2)

#change label position
p2$data[[2]]$x <- p2$data[[2]]$x - .5

#rebuild graph
grid.draw(ggplot_gtable(p2))
#clear graph
dev.off()