着色方案餅圖，ggplot2

Question

我正在用ggplot2制作餅圖，但我無法正確獲取餅圖的顏色。

df <- data.frame(group = c("Information technology", "Laboratory", "Tools", 
                           "Unspecified", "Other"), 
                 value = c(2500, 2000, 1500, 1000, 4000))

# Coloring scheme
blue1 <- "#0a3250"   # darkest blue
blue2 <- "#13517b"
blue3 <- "#2f659f"
blue4 <- "#518ecb"
blue5 <- "#aac8df"
blue6 <- "#d6e7f2"   # lightest blue
colorscheme <- scale_fill_manual(values = c(blue1, blue2, blue3,
                                            blue4, blue5, blue6))
# Data labels: 
df   <- df[!is.na(df$value),]   # Only keeps non-zero segments
lbls <- df$value/sum(df$value)
lbls <- percent(lbls)           # Converts to string and adds % sign
lbls[lbls == "0.0%"] <- ""      # Removes 0.0% as a label

# we now actually plot the data:
ggplot(df, aes(x = "", y = value, fill = group)) +   
    colorscheme +
    geom_bar(width = 1, stat = "identity", col = "white") + 
    xlab("") + ylab("") + 
    theme_bw() + 
    geom_text(aes(x     = 1.90, 
                  y     = value/2 + c(0, cumsum(value)[-length(value)]), 
                  label = lbls), size = 4) + 
    coord_polar(theta = "y") + 
    theme(
      axis.text       = element_blank(), 
      panel.grid      = element_blank(),
      panel.border    = element_blank(),
      legend.key      = element_rect(fill=NULL, colour = "white"),
      legend.key.size = unit(0.5, "cm"),
      legend.title    = element_blank(),
      legend.text     = element_text(size = 9)
)

我想要的是：

我希望df的第一個條目具有顏色blue1 ，第二個條目blue2等。這樣切片按順時針順序從最深的藍色到最淺的藍色。 此外，圖例應以與df相同的順序顯示組。

問題是什么：

但是，顏色不是根據df位置分配的，而是根據字母順序分配的。 現在，不同深淺的藍色散布在餅圖和圖例上。

Answer 1

為您的分類變量使用一個因子：

df <- data.frame(group=factor(x=1:5, 
         labels=c("Information technology", "Laboratory", "Tools", "Unspecified", "Other")), 
                 value = c(2500, 2000, 1500, 1000, 4000))