如何使用 ggplot 和 purrr 在同一图表上绘制由数据框中的索引选择的线？

Question

我有索引列表

l <- list(a = sample(1:nrow(mpg), 10), b = sample(1:nrow(mpg), 15), c = sample(1:nrow(mpg), 10),
          d = sample(1:nrow(mpg), 12), e = sample(1:nrow(mpg), 17))

我尝试在同一张图上绘制存储在 l 中的索引选择的线。是否可以使用 purrr 压缩下一个表达式？

library(tidyverse)
ggplot() +
  geom_line(data = mpg[l$a, ], aes(x = displ, y = cty), color = RColorBrewer::brewer.pal(5, "Set2")[1]) +
  geom_line(data = mpg[l$b, ], aes(x = displ, y = cty), color = RColorBrewer::brewer.pal(5, "Set2")[2]) +
  geom_line(data = mpg[l$c, ], aes(x = displ, y = cty), color = RColorBrewer::brewer.pal(5, "Set2")[3]) +
  geom_line(data = mpg[l$d, ], aes(x = displ, y = cty), color = RColorBrewer::brewer.pal(5, "Set2")[4]) +
  geom_line(data = mpg[l$e, ], aes(x = displ, y = cty), color = RColorBrewer::brewer.pal(5, "Set2")[5])

Answer 1

您可以构建一个新的数据集来绘制数据：

df = numeric() #Empty starting point
for(i in 1:length(l)){
  df = rbind(df, cbind(mpg[l[[i]],], name=names(l)[i]))}
#Rbind the last iteration with the mpg on the indexes + a column with the name of the index

ggplot(df, aes(x=displ, y=cty, color=name)) +
  geom_line()

您可以使用 scale_color_brewer() 更改调色板。

输出：

Answer 2

调出数据框的相关行，并提供相应名称的列：

library(tidyverse)
data(mpg)

mpg[unlist(l),] %>%
mutate(data =  rep(names(l),lengths(l))) %>%
ggplot() +
geom_line(aes(x = displ, y = cty,color = data)) +
scale_color_manual(values=RColorBrewer::brewer.pal(5, "Set2"))

Answer 3

library(tidyverse)

l <- list(a = sample(1:nrow(mpg), 10), b = sample(1:nrow(mpg), 10), c = sample(1:nrow(mpg), 10),
          d = sample(1:nrow(mpg), 10), e = sample(1:nrow(mpg), 10))

# Generate a list of ggplot layers to add to the final plot
layer_list <- map2(.x = l,
                   .y = seq_along(l),
                   .f = ~ geom_line(data = mpg[.x, ], aes(x = displ, y = cty),
                                    color = RColorBrewer::brewer.pal(5, "Set2")[.y]))

# Build the final plot
ggplot(data = mpg) +
  layer_list

如何使用 ggplot 和 purrr 在同一图表上绘制由数据框中的索引选择的线？

How to plot lines selected by indices from dataframe on the same graph with ggplot and purrr?

r

ggplot2

purrr