如何在 geom_smooth 之后而不是在 geom_line 之后显示直接标签？

Question

我正在使用直接标签来注释我的情节。正如你在这张图片中看到的，标签在 geom_line 之后，但我想要在 geom_smooth 之后。这是否受直接标签支持？或任何其他想法如何实现这一目标？提前致谢！

这是我的代码：

library(ggplot2)
library(directlabels)

set.seed(124234345)

# Generate data
df.2 <- data.frame("n_gram" = c("word1"),
                   "year" = rep(100:199),
                   "match_count" = runif(100 ,min = 1000 , max = 2000))

df.2 <- rbind(df.2, data.frame("n_gram" = c("word2"),
                      "year" = rep(100:199),
                      "match_count" = runif(100 ,min = 1000 , max = 2000)) )

# plot
ggplot(df.2, aes(year, match_count, group=n_gram, color=n_gram)) +
  geom_line(alpha = I(7/10), color="grey", show_guide=F) +
  stat_smooth(size=2, span=0.3, se=F, show_guide=F) +
  geom_dl(aes(label=n_gram), method = "last.bumpup", show_guide=F) +
  xlim(c(100,220))

Answer 1

这个答案采用了 @celt-Ail 答案的基本概念，而不是函数、基础 R 和直接标签，而是尝试了 tidyverse 方法，从这里窃取了多个loess模型的一些代码。

很高兴听到改进建议。

set.seed(124234345)

# Generate data
df.2 <- data.frame("n_gram" = c("word1"),
                   "year" = rep(100:199),
                   "match_count" = runif(100 ,min = 1000 , max = 2000))

df.2 <- rbind(df.2, data.frame("n_gram" = c("word2"),
                               "year" = rep(100:199),
                               "match_count" = runif(100 ,min = 1000 , max = 2000)) )

#example of loess for multiple models
#/sf/answers/3858924121/
library(dplyr)
library(tidyr)
library(purrr)
library(ggplot2)

models <- df.2 %>%
  tidyr::nest(-n_gram) %>%
  dplyr::mutate(
    # Perform loess calculation on each CpG group
    m = purrr::map(data, loess,
                   formula = match_count ~ year, span = .3),
    # Retrieve the fitted values from each model
    fitted = purrr::map(m, `[[`, "fitted")
  )

# Apply fitted y's as a new column
results <- models %>%
  dplyr::select(-m) %>%
  tidyr::unnest()

#find final x values for each group
my_last_points <- results %>% group_by(n_gram) %>% summarise(year = max(year, na.rm=TRUE))

#Join dataframe of predictions to group labels
my_last_points$pred_y <- left_join(my_last_points, results)

# Plot with loess line for each group
ggplot(results, aes(x = year, y = match_count, group = n_gram, colour = n_gram)) +
  geom_line(alpha = I(7/10), color="grey", show.legend=F) +
  #stat_smooth(size=2, span=0.3, se=F, show_guide=F)
  geom_point() +
  geom_line(aes(y = fitted))+  
  geom_text(data = my_last_points, aes(x=year+5, y=pred_y$fitted, label = n_gram))

Answer 2

我要在这里回答我自己的问题，因为我通过泰勒·林克的回复找到了答案。

这就是我使用 loess() 获取标签位置来解决它的方法。

 # Function to get last Y-value from loess
funcDlMove <- function (n_gram) {

  model <- loess(match_count ~ year, df.2[df.2$n_gram==n_gram,], span=0.3)
  Y <- model$fitted[length(model$fitted)]
  Y <- dl.move(n_gram, y=Y,x=200)
  return(Y)
}

index <- unique(df.2$n_gram)
mymethod <- list(
  "top.points", 
  lapply(index, funcDlMove)
  )

# Plot

PLOT <- ggplot(df.2, aes(year, match_count, group=n_gram, color=n_gram)) +
  geom_line(alpha = I(7/10), color="grey", show_guide=F) +
  stat_smooth(size=2, span=0.3, se=F, show_guide=F)

direct.label(PLOT, mymethod)

这将生成此图：https://i.stack.imgur.com/FGK1w.png