introduce a method to keep original radius to legend

[xiangpin]

keep the original radius to legend

the related issue #39

But I don't think we might need to introduce a new argument, I use options to control.

library(ggforce)                                                                                                                                                                                                   library(ggplot2)
library(scatterpie)
library(aplot)

countries <- map_data("world")

radius <- c(log(2), log(31), log(151), log(751))
labeller <- function(x) round(exp(x) - 1, digits = 0)

Plot3.dat <- structure(list(Country = structure(1:28, levels = c("Australia",
"Belgium", "Cambodia", "Canada", "Ecuador", "England", "Ethiopia",
"France", "French Polynesia", "Germany", "India", "Indonesia",
"Iran", "Israel", "Japan", "Malaysia", "Mexico", "Mongolia",
"Morocco", "New Zealand", "Pakistan", "Philipines", "Spain",
"Switzerland", "Thailand", "United Kingdom", "United States of America",
"Wales"), class = "factor"), Carnivore = c(566L, 0L, 0L, 0L,
2L, 0L, 3L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 147L,
0L, 0L, 0L, 1L, 0L, 0L, 88L, 0L), Herbivore = c(242L, 0L, 0L,
34L, 0L, 0L, 0L, 5L, 0L, 0L, 0L, 0L, 0L, 3L, 0L, 0L, 0L, 0L,
0L, 46L, 0L, 0L, 0L, 0L, 0L, 0L, 79L, 0L), Omnivore = c(130L,
1L, 24L, 2L, 0L, 161L, 0L, 5L, 1L, 17L, 409L, 5L, 6L, 0L, 4L,
11L, 4L, 2L, 1L, 728L, 278L, 4L, 6L, 0L, 27L, 10L, 282L, 1L),
    lat = c(-25.2744, 50.5039, 12.5657, 56.1304, -1.8312, 52.3555,
    9.145, 46.2276, -17.6797, 51.1657, 20.5937, -0.7893, 32.4279,
    31.0461, 36.2048, 4.2105, 23.6345, 46.8625, 31.7917, -40.9006,
    30.3753, 12.8797, 40.4637, 46.8182, 15.87, 55.3781, 37.0902,
    52.1307), long = c(133.7751, 4.4699, 104.991, -106.3468,
    -78.1834, -1.1743, 40.4897, 2.2137, -149.4068, 10.4515, 78.9629,
    113.9213, 53.688, 34.8516, 138.2529, 101.9758, -102.5528,
    103.8467, -7.0926, 174.886, 69.3451, 121.774, -3.7492, 8.2275,
    100.9925, -3.436, -95.7129, -3.7837), Prop.carn = c(0.603411513859275,
    0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.159609120521173,
    0, 0, 0, 1, 0, 0, 0.195991091314031, 0), Prop.herb = c(0.257995735607676,
    0, 0, 0.944444444444444, 0, 0, 0, 0.5, 0, 0, 0, 0, 0, 1,
    0, 0, 0, 0, 0, 0.0499457111834962, 0, 0, 0, 0, 0, 0, 0.175946547884187,
    0), Prop.om = c(0.138592750533049, 1, 1, 0.0555555555555556,
    0, 1, 0, 0.5, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0.790445168295331,
    1, 1, 1, 0, 1, 1, 0.628062360801782, 1), radius = c(938,
    1, 24, 36, 2, 161, 3, 10, 1, 17, 409, 5, 6, 3, 4, 11, 4,
    2, 1, 921, 278, 4, 6, 1, 27, 10, 449, 1), lradius = c(6.84481547920826,
    0.693147180559945, 3.2188758248682, 3.61091791264422, 1.09861228866811,
    5.08759633523238, 1.38629436111989, 2.39789527279837, 0.693147180559945,
    2.89037175789616, 6.01615715969835, 1.79175946922805, 1.94591014905531,
    1.38629436111989, 1.6094379124341, 2.484906649788, 1.6094379124341,
    1.09861228866811, 0.693147180559945, 6.82654522355659, 5.63121178182137,
    1.6094379124341, 1.94591014905531, 0.693147180559945, 3.3322045101752,
    2.39789527279837, 6.10924758276437, 0.693147180559945)), row.names = c(NA,
-28L), class = "data.frame")

p1 <- ggplot() +
  geom_polygon(
    data = countries,
    aes(x = long, y = lat, group = group),
    colour = "black", fill = NA
  )

p2 <- p1 +
  geom_scatterpie(
    data = Plot3.dat,
    aes(x = long, y = lat, r = lradius),
    sorted_by_radius = T,
    cols = c("Prop.carn", "Prop.herb", "Prop.om")
  ) +
  coord_quickmap()

options(scatterpie_legend_breaks = NULL)
p3 <- p2 +
      geom_scatterpie_legend(
         radius = radius,
         x = -150.54, y = -50, n = 5,
         labeller = labeller
      )

options(scatterpie_legend_breaks = radius)
p4 <- p2 +
      geom_scatterpie_legend(
         radius = radius,
         x = -150.54, y = -50, n = 5,
         labeller = labeller
      )

p3 / p4           

[GuangchuangYu]

IMO, introducing a parameter, break, is preferred in this case.

[xiangpin]

ok, using breaks argument instead of using options