Using logic in listcols (ggplot2 edition)-CodePudding

I am trying to produce a slightly different result from a purrr::map iteration depending on a condition. Say I have this code producing plots and storing them in a dataframe:

library(tidyverse)
#> -- Attaching packages --------------------------------------- tidyverse 1.3.1 --
#> v ggplot2 3.3.5     v purrr   0.3.4
#> v tibble  3.1.6     v dplyr   1.0.7
#> v tidyr   1.1.4     v stringr 1.4.0
#> v readr   2.1.0     v forcats 0.5.1
#> -- Conflicts ------------------------------------------ tidyverse_conflicts() --
#> x dplyr::filter() masks stats::filter()
#> x dplyr::lag()    masks stats::lag()

plots <- iris |>
  group_by(Species) |>
  nest() |>
  mutate(plot = map(data, ~ {
    ggplot(.x)  
      geom_point(aes(x = Sepal.Length, y = Sepal.Width, fill = Petal.Width))
  }))

Say I only wanted to the first plot (or Species == "setosa", whatever) to have a legend like so:

plots$plot[[1]]

Then subsequent plots would have no legend like so:

plots$plot[[2]]  
  guides(fill = "none")

Is there anyway to do that directly in the mutate/map call?

CodePudding user response：

Use cur_group_id() to identify the current group. There are also other helper functions like cur_group(), which could give you even finer control over the operations to be done within each group.

library(dplyr)
library(tidyr)
library(ggplot2)
library(purrr)

plots <- iris |>
  group_by(Species) |>
  nest() |>
  mutate(plot = map(data, ~ {
    ggplot(.x)  
      geom_point(aes(x = Sepal.Length, y = Sepal.Width, fill = Petal.Width))   
      if (cur_group_id() > 1L) guides(fill = "none")
  }))

CodePudding user response：

You could add a column showlegend to your nested data, use map2 to loop over both data and showlegend and inside your plotting function remove the legend if showlegend == FALSE:

library(ggplot2)
library(purrr)
library(dplyr)
library(tidyr)

plots <- iris |>
  group_by(Species) |>
  nest() |>
  mutate(
    showlegend = Species == "setosa",
    plot = map2(data, showlegend, ~ {
      guide <- if (!showlegend) guides(fill = "none")
      ggplot(.x)  
        geom_point(aes(x = Sepal.Length, y = Sepal.Width, fill = Petal.Width))  
        guide
    })
  )

plots$plot[[1]]

plots$plot[[2]]