r - 如何为 scale_fill_distiller 设置颜色条

Question

我正在绘制一个“圆圈包装图”，圆圈的颜色映射到一个值：

    # libraries
library(packcircles)
library(ggplot2)

# Create data
data=data.frame(group=paste("Group", letters[1:20]), value=sample(seq(1,100),20)) 

# Generate the layout. This function return a dataframe with one line per bubble. 
# It gives its center (x and y) and its radius, proportional of the value
packing <- circleProgressiveLayout(data$value, sizetype='area')

# We can add these packing information to the initial data frame
data = cbind(data, packing)

# Check that radius is proportional to value. We don't want a linear relationship, since it is the AREA that must be proportionnal to the value
plot(data$radius, data$value)

# The next step is to go from one center + a radius to the coordinates of a circle that
# is drawn by a multitude of straight lines.
dat.gg <- circleLayoutVertices(packing, npoints=50)
dat.gg$value=rep(data$value, each=51)
# Make the plot
ggplot() + 

 # Make the bubbles
  geom_polygon(data = dat.gg, aes(x, y, group = id, fill=value), colour = "black", alpha = 0.6) +
  scale_fill_distiller(palette = "BuPu", direction = 1 , guide="colourbar") +  

  # Add text in the center of each bubble + control its size
  geom_text(data = data, aes(x, y, size=value, label = group)) +
  scale_size_continuous(range = c(1,4)) +

  # General theme:
  theme_void() + 
  theme(legend.position="none") +
  coord_equal()

我想在绘图旁边显示一个颜色条，所以我尝试了这条线：

  scale_fill_distiller(palette = "BuPu", direction = 1 , guide="colourbar")

但这不起作用（不显示彩条）。什么是正确的语法？

标签： rggplot2