多行的每行一個線圖（ggplot 或 base R？）

Question

我有以下數據框：

test_new <- structure(list(PS_position = c(12871487, 12997222, 12861487, 
 12871491, 12934355), Region_ID = structure(c(1L, 1L, 2L, 2L, 
 1L), .Label = c("D", "D_left", "D_right"), class = "factor"), 
 chr_key = c(1, 1, 1, 1, 1), start = c(12871487, 12871487, 
 12871487, 12871487, 12871487), stop = c(12997222, 12997222, 
 12997222, 12997222, 12997222), exact_center = c(12934355, 
 12934355, 12934355, 12934355, 12934355)), .Names = c("PS_position", 
 "Region_ID", "chr_key", "start", "stop", "exact_center"), row.names = c(1L, 
 2L, 3L, 4L, 7L), class = "data.frame")

我想為每行繪制一個圖，其中每個區域的開始、停止和中心保持不變，並且 PS_position 被逐個添加為一個點，如下所示（圖上不需要有文字，PS_position 標記可以是別的）：

這在 ggplot 中作為 geom_vline() 和 geom_hline() 很難做到：

ggplot(test_new) + geom_vline(xintercept = 12871487) + geom_vline(xintercept = 12997222) + geom_vline(xintercept = 12934355)

所以我用一個例子嘗試了 base R：

plot(1,1)
lines(c(0.8, 1.2), c(0.6, 0.6))
abline(v = 1, col = "gray60")
abline(v=1.2, col = "gray60")
abline(v=0.8, col = "gray60")

很明顯，這些策略離期望的情節還有很長的路要走。 所以我的問題是如何最好地為單行制作所需的圖，以及如何迭代它以保持前一行的點數？

非常感謝！

Answer 1

Reduce(
  function(plot, position) {
    plot + annotate(
      geom = "point", 
      x = position, y = 1, 
      shape = 18, size = 5)
  }, 
  test_new$PS_position, 
  init = ggplot() + 
    theme_minimal() +
    theme(
      panel.grid =element_blank(),
      axis.text = element_blank(),
      axis.line = element_blank()) +
    labs(x = NULL, y = NULL) +
    geom_vline(xintercept = c(12871487, 12934355, 12997222), color = "red"),
  accumulate = TRUE)

將構建一個包含迭代添加點的圖列表，看起來非常接近您的想法，最后一個圖看起來像這樣

編輯

使用 dplyr、tidyr 和 purrr 按數據框分組。 這只是按 Region_ID 分組，為列中的每個數據幀嵌套和運行相同的減少

library(dplyr)
library(purrr)
library(tidyr)

test_new %>%
  group_by(Region_ID) %>%
  nest() %>%
  mutate(plots = map(data, ~Reduce(
    function(plot, position) {
      plot + annotate(
        geom = "point", 
        x = position, y = 1, 
        shape = 18, size = 5)
    }, 
    .$PS_position, 
    init = ggplot() + 
      theme_minimal() +
      theme(
        panel.grid =element_blank(),
        axis.text = element_blank(),
        axis.line = element_blank()) +
      labs(x = NULL, y = NULL) +
      geom_vline(xintercept = c(12871487, 12934355, 12997222), color = "red"),
    accumulate = TRUE)))