geom_text 在饼图中的某个位置

Question

我想创建一个饼图，在特定位置显示一些标签，表示比例检验是否显着。我设法创建了一个基本的饼图，并粘贴了下面的代码。我还发布了所需的结果（使用 MS Paint 软件创建），并希望在创建此图时能得到任何帮助。

library(tidyverse)

# defining the dataframe
df <-
  data.frame(
    condition = c('x', 'y', 'z'),
    cat = rep(c('a', 'b'), 3),
    freq = c(60, 34, 44, 40, 66, 56)
  )

# computing percentages
df <-
  df %>% group_by(condition) %>% mutate(label = freq / sum(freq) * 100)

# creating a pie chart
ggplot2::ggplot(data = df, mapping = aes('', freq, fill = cat)) +
  facet_grid(". ~ condition") +
  geom_col(position = 'fill') +
  geom_label(aes(label = label), position = position_fill(vjust = 0.5)) +
  coord_polar(theta = 'y') +
  ggplot2::scale_y_continuous(breaks = NULL)  +
  ggplot2::theme_grey() +
  ggplot2::theme(
    panel.grid = element_blank(),
    axis.ticks = element_blank(),
    axis.title = element_blank(),
    axis.text.x = element_blank(),
    axis.text.y = element_blank(),
    strip.text.x = element_text(size = 14, face = "bold"),
    strip.text.y = element_text(size = 14, face = "bold"),
    strip.text = element_text(size = 14, face = "bold"),
    legend.text = element_text(size = 14),
    legend.title = element_text(size = 14, face = "bold"),
    legend.title.align = 0.5,
    legend.text.align = 0.5,
    legend.direction = "horizontal",
    legend.position = "bottom",
    legend.key = element_rect(size = 5),
    legend.key.size = unit(1.5, "lines"),
    legend.margin = margin(5, 5, 5, 5),
    legend.box.margin = margin(5, 5, 5, 5),
    panel.border = element_rect(
      colour = "black",
      fill = NA,
      size = 1
    ),
    plot.subtitle = element_text(
      color = "black",
      size = 14,
      hjust = 0.5
    ),
    plot.title = element_text(
      color = "black",
      size = 16,
      face = "bold",
      hjust = 0.5
    )
  ) +
  ggplot2::guides(fill = guide_legend(override.aes = base::list(colour = NA)))

由 reprex package (v0.2.0) 创建于 2018-03-21。

这是所需结果的样子（请注意，文本始终位于顶部并与饼图的中心对齐）-

Answer 1

这个怎么样？我使用 geom_text 并指定 x = 1.6 来获取饼图半径之外的标签。另外，这只是一个样式提示，但是在 theme() 中有很多不必要的参数，并且在加载 tidyverse 后不需要在 ggplot 函数之前放置 ggplot2::。此外，如果您不希望饼图的中心有一个小的空点，您可以在调用 geom_col.

时添加 width = 1

    library(tidyverse)

    df <-
      data.frame(
        condition = c('x', 'y', 'z'),
        cat = rep(c('a', 'b'), 3),
        freq = c(60, 34, 44, 40, 66, 56), 
        sig =c("***", NA, "ns", NA, "**", NA)
      ) %>% 
      group_by(condition) %>% 
      mutate(label = freq / sum(freq) * 100)

    ggplot(data = df, mapping = aes('', freq, fill = cat)) +
      facet_wrap(~ condition, nrow = 1) +
      geom_col(position = 'fill', width = 1) +
      geom_label(aes(label = label), position = position_fill(vjust = 0.5)) +
      geom_text(aes(label = sig, x = 1.6), position = position_fill(vjust = 1)) +
      coord_polar(theta = 'y') +
      theme_grey() +
      theme(panel.grid = element_blank(),
            axis.ticks = element_blank(),
            axis.text = element_blank(),
            axis.title = element_blank(),
            strip.text = element_text(size = 14, face = "bold"),
            strip.background = element_rect(color = "black", size = 1),
            legend.text = element_text(size = 14),
            legend.title = element_text(size = 14, face = "bold"),
            legend.position = "bottom",
            legend.key.size = unit(1.5, "lines"),
            panel.border = element_rect(colour = "black", fill = NA, size = 1)) +
      guides(fill = guide_legend(override.aes = list(colour = NA)))

Here's the result

geom_text 在饼图中的某个位置

geom_text at certain position in a pie chart

r

ggplot2

tidyverse