labels outside pie chart. convert to percentage and display number

[saurabh]

tata3 <- data.frame(Subtype = c("Prostate", "Oesophagus", "Breasr"), alive = c(88, 22, 100), dead = c(12, 55, 17), uncertain = c(10, 2, 2), total = c(186,46,202))

Above is dataframe. I then tried code below to get a pie chart

ggplot(tata3, aes(x = "", y = total, fill=Subtype)) + geom_col(width=1, color=1) + coord_polar(theta = "y") + geom_label_repel(data=tata3, aes(y= total, label = paste0(total)), size = 3, nudge_x = 3, show.legend = FALSE)

Hello, I want the following if possible
1)The label to appear more neatly - as per the graph you can see the lines on the labels really are not positioned properly
2) Any way of making the values for each pie chart that are displayed also appear in percentages next to it, ideally by incorporating the library(scales) package.

Thanks very much

[saurabh]

just to say I've tried various permutations of y_nudge and x_nudge...still hasnt worked.

[andresrcs]

Polar coordinates for geom_label_repel() need to be manually calculated.

library(tidyverse)
library(ggrepel)

tata3 <- data.frame(
    Subtype = c("Prostate", "Oesophagus", "Breasr"),
    alive = c(88, 22, 100), dead = c(12, 55, 17),
    uncertain = c(10, 2, 2), total = c(186,46,202))

tata3 %>% 
    mutate(csum = rev(cumsum(rev(total))), 
           pos = total/2 + lead(csum, 1),
           pos = if_else(is.na(pos), total/2, pos),
           percentage = total/sum(total)) %>% 
    ggplot(aes(x = "", y = total, fill = fct_inorder(Subtype))) + 
    geom_col(width = 1, color = 1) +
    geom_label_repel(aes(y = pos,
                         label = glue::glue("{total} ({scales::percent(percentage)})"), 
                         fill = Subtype),
                     size = 3,
                     nudge_x = 3,
                     show.legend = FALSE) +
    labs(  fill = "Subtype" ) +
    coord_polar(theta = "y") +
    theme_void()

^{Created on 2022-02-27 by the reprex package (v2.0.1)}

[saurabh]

many thanks.

I'd also quite like to understand with the code below means..

csum = rev(cumsum(rev(total))), 
pos = total/2 + lead(csum, 1),
pos = if_else(is.na(pos), total/2, pos),
percentage = total/sum(total)) 

I can see its trying to convert the values into percentages...but I'm not sure exactly what each line does. Thanks

[andresrcs]

@saurabh

csum = rev(cumsum(rev(total))),

This gets the cumulative sum of your total values

@saurabh

pos = total/2 + lead(csum, 1),

This gets the mid position for each Subtype label

@saurabh

pos = if_else(is.na(pos), total/2, pos),

This replaces the NA introduced by the use of lead()

@saurabh

percentage = total/sum(total))

This calculates the percentage for each Subtype

[saurabh]

Many thanks.

Also, I 've tried using geom_text to get the Subtype categorical variable name to appear within its respective slice of the piechart. This does not seem to work and the variable 'Prostate' etc all seem to appear haphazardly in the chart.

1. Is there any way of achieving the above?
2. The lines within the piechart appear a bit frazzled in output from my PC. These dark lines appear quite smooth here...is there anything I can do about this?

Thanks Again