R Plotly: how to order pie chart?

Question

I\'m using the plotly package in R to build an R Shiny dashboard. I want to order my pie chart in a custom order (non-alphabetic, non-descending/ascending order

Answer 1

Ok, the answer is apparently twofold. Firstly, there is an argument in plot_ly, asking to sort the data on values (default is TRUE) or work with the custom order. Change this to FALSE.

Then, secondly, the order (clockwise) is different from the order in the data frame. The pie starts in the top right corner, and continues counterclockwise.

Hence, the following solves the problem:

# Get Manufacturer
mtcars$manuf <- sapply(strsplit(rownames(mtcars), " "), "[[", 1)

df <- mtcars %>%
  group_by(manuf) %>%
  summarize(count = n())

# Create custom order
customOrder <- c(df$manuf[12:22],df$manuf[1:11])

# Adjust customOrder to deal with pie
customOrder <- c(customOrder[1],rev(customOrder[2:length(customOrder)]))

# Order data frame
df <- df %>% slice(match(customOrder, manuf))

# Create factor
df$manuf <- factor(df$manuf, levels = df[["manuf"]])

# Plot
df %>% plot_ly(labels = ~manuf, values = ~count, sort = FALSE) %>%
  add_pie(hole = 0.6) %>%
  layout(title = "Donut charts using Plotly",  showlegend = F,
         xaxis = list(showgrid = FALSE, zeroline = FALSE, showticklabels = FALSE),
         yaxis = list(showgrid = FALSE, zeroline = FALSE, showticklabels = FALSE))