R: Hide some parts of ggplot legend-CodePudding

I'm trying to plot a facetted box plot of some data, including the outliers with colours, a mark showing group mean (created with stat_summary), as well as a horizontal line marking the average value of the facet group. I would like to have a legend for the horizontal line (denoting the facet group average) and the box plot mark (denoting the group means within each facet). I've tried quite a few approaches thus far, from testing out the show.legend argument in every geom, fiddling with different inputs to scale_colour_manual (e.g.

library(tidyverse)
library(ggsci)

df <- as_tibble(msleep) %>% 
    mutate(bodywt_log10 = log10(bodywt)) %>% 
    pivot_longer(cols = c(sleep_total, awake, bodywt_log10),
                 names_to = 'stat', values_to = 'value') %>% 
    select(-c('sleep_rem', 'sleep_cycle', 'brainwt', 'bodywt')) %>% 
    mutate(stat = factor(stat, levels = unique(stat))) %>% 
    group_by(stat) %>% 
    mutate(mean = mean(value)) %>% 
    group_by(stat, order) %>% 
    mutate(Q1 = quantile(value, 1/4, na.rm = T),
           Q2 = quantile(value, 2/4, na.rm = T),
           Q3 = quantile(value, 3/4, na.rm = T),
           IQR = IQR(value, na.rm = T),
           upper.limit=Q3 1.5*IQR, 
           lower.limit=Q1-1.5*IQR)

outlier_dat <- df %>%
    filter(value > upper.limit | value < lower.limit)

pal <- pal_npg('nrc')(3)

df %>% 
    ggplot(aes(x = order, y = value))   
    geom_boxplot(show.legend = F, outlier.shape = NA, aes(col = stat))  
    geom_boxplot(outlier.shape = NA, show.legend = F, aes(fill = stat))  
    stat_summary(fun = mean, geom = 'point', shape = 18, size = 3, aes(col = 'group_mean'), show.legend = T)  
    facet_grid(stat~., scales = 'free', labeller = as_labeller(
        c(sleep_total = 'Total sleep', awake = 'Time awake', bodywt_log10 = 'log10(Bodyweight)')))   
    geom_hline(aes(yintercept = mean, col = 'mean'), size = .75, lty = 2, show.legend = T)  
    scale_fill_npg()   
    scale_colour_manual(name = NULL, values = c('mean' = 'black', 'group_mean' = 'gray10', 
                                                'sleep_total' = pal[1], 'awake' = pal[2], 'bodywt_log10' = pal[3]),
                        breaks = c('mean', 'group_mean'), labels = c('Overall mean', 'Group mean'),
                        guide = guide_legend(override.aes = list(linetype = c('dashed', 'blank'), shape =  c(NA, 18))))  
    geom_point(data = outlier_dat, aes(col = stat), size = 2, show.legend = F)

CodePudding user response：

Add the following:

  guides(fill = "none")

You have one legend (guide) for each aes mapping - your faceting variables are a fill scale (each facet has a different fill colour) whereas the means are a color/colour scale (i.e. the line/point colour rather than fill). Setting the guide for the "fill" colour to "none" removes it from the plot.

CodePudding user response：

Just add

df   guides(fill="none")