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rcountpanelfacetfacet-grid

Add n of unique id to panel title (facet_grid)

for this dataset

structure(list(triplet_id = c("100_2015-11-26_2016-11-09_2017-12-06", 
"100_2015-11-26_2016-11-09_2017-12-06", "100_2015-11-26_2017-02-15_2017-12-06", 
"100_2015-11-26_2017-02-15_2017-12-06", "100_2015-11-26_2017-02-15_2018-05-09", 
"100_2015-11-26_2017-02-15_2018-05-09", "100_2016-05-11_2017-02-15_2017-12-06", 
"100_2016-05-11_2017-02-15_2017-12-06", "100_2016-05-11_2017-02-15_2018-05-09", 
"100_2016-05-11_2017-02-15_2018-05-09"), age_group = structure(c(2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L), levels = c("<5", "5-9", "10-18", ">18"), class = "factor"), 
    visit_type = c("visit_number", "visit_number", "visit_number", 
    "visit_number", "visit_number", "visit_number", "visit_number", 
    "visit_number", "visit_number", "visit_number"), visit_type_1 = c("visit2", 
    "visit3", "visit2", "visit3", "visit2", "visit3", "visit2", 
    "visit3", "visit2", "visit3"), Item = structure(c(1L, 1L, 
    1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), levels = c("1", "2", "3", 
    "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", "14", 
    "15", "16", "17", "18", "19"), class = "factor"), Item_score = structure(c(2L, 
    2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L), levels = c("-1", "0", 
    "1"), class = "factor")), row.names = c(NA, -10L), class = c("tbl_df", 
"tbl", "data.frame"))

I want to add the total unique ID (triplet_id) to each panel title for each age_group. I wrote this code, but it doesn't work, neither for the position of the text nor for the actual count

pl <- ggplot(data = graph,aes(y= Item, fill = Item_score))+ 
  geom_bar(stat="count", position = position_fill(reverse = TRUE),color = "black") + 
  scale_y_discrete(limits=rev)+
  scale_fill_manual(values = c("red", "white", "seagreen3"))+
  theme_classic() + 
  labs(y ="items\n", x = "Percentage")+ 
  scale_x_continuous(labels = scales::percent,breaks = seq(0, 1, .25))+
  facet_grid(visit_type_1~age_group,  labeller = labeller(visit_type_1 = time.labs))+
  theme(legend.position = "none",text = element_text(size = 30),strip.text.x = element_text(size = 30),
        strip.text.y = element_text(size = 30),panel.spacing.x=unit(1.5, "lines"),panel.spacing.y=unit(2, "lines"))+
  geom_text(aes(label = paste0("Count: ", length(unique(triplet_id)))), 
            x = 5, y = 5)+
  labs(title = "A")
pl

do you have any suggestion? Thank you

Solution

  • You can create a custom labeller function that counts unique triplet IDs and returns the count for each age_group:

    label_func <- function(age_grp) {
  n_triplet_ids <- df |> 
    count(age_group, triplet_id) |> 
    count(age_group) |> 
    pull(var = n)
  
  return(paste0("Age Group: ", age_grp, "  (N triplets: ", n_triplet_ids, ")"))
}

df |> 
  ggplot(aes(y = Item, fill = Item_score)) + 
  geom_bar(stat="count") + 
  facet_grid(visit_type_1 ~ age_group,  
             labeller = labeller(age_group = label_func))

    enter image description here Notes:

    • Updated data slightly to show some variability in groups
    • Left out extra ggplot styling

    Updated data:

    # A tibble: 10 × 6
   triplet_id                           age_group visit_type   visit_type_1 Item  Item_score
   <chr>                                <fct>     <chr>        <chr>        <fct> <fct>     
 1 100_2015-11-26_2016-11-09_2017-12-06 5-9       visit_number visit2       1     0         
 2 100_2015-11-26_2016-11-09_2017-12-06 5-9       visit_number visit3       1     0         
 3 100_2015-11-26_2017-02-15_2017-12-06 5-9       visit_number visit2       1     0         
 4 100_2015-11-26_2017-02-15_2017-12-06 5-9       visit_number visit3       1     0         
 5 100_2015-11-26_2017-02-15_2018-05-09 5-9       visit_number visit2       1     -1        
 6 100_2015-11-26_2017-02-15_2018-05-09 5-9       visit_number visit3       1     -1        
 7 100_2016-05-11_2017-02-15_2017-12-06 5-9       visit_number visit2       1     0         
 8 100_2016-05-11_2017-02-15_2017-12-06 10-18     visit_number visit3       1     0         
 9 100_2016-05-11_2017-02-15_2018-05-09 10-18     visit_number visit2       1     0         
10 100_2016-05-11_2017-02-15_2018-05-09 10-18     visit_number visit3       1     -1