將圖例添加到具有不同類型美學的ggplot直方圖中

Question

我想為我的一個情節添加一個圖例，但我有不同的美學，我從未創造過一個傳奇，所以我發現很難確定如何構建它。

我的一個美學是填充代碼，我手動添加為矢量。 另一種美學是我用geom_vline添加的垂直線。

從下圖中，我想要添加到圖例中的三個特征：1）顏色為深藍色的條形圖，2）顏色為淺藍色的條形圖和3）垂直線條。

有沒有人建議我如何有效地編碼？

#df
df <- data.frame(Time_Diff <- runif(1000, 0, 200))


# Show median, IQR range and outliers
colors <- c(rep("blue",3), rep("paleturquoise2",38))
bp_overall <- ggplot(data = df, aes(Time_Diff)) 
bp_overall + 
  geom_histogram(binwidth = 5, fill = colors) + #create histogram
  ggtitle("Time Difference")  +
  xlab("Time in Days") +
  ylab("Amount") +
  geom_vline(xintercept = 3, linetype = "twodash", size = 1,      colour= "darkblue") + #show median
  scale_x_continuous(breaks = seq(0, 202, 10)) +
  theme_light() +
  theme(panel.grid.minor = element_blank(),
    panel.border = element_blank(), #remove all border lines
    axis.line.x = element_line(size = 0.5, linetype = "solid", colour = "black"), #add x-axis border line
    axis.line.y = element_line(size = 0.5, linetype = "solid", colour = "black")) + #add y-axis border line
  theme(plot.title = element_text(family = windowsFont("Verdana"),     color="black", size=14, hjust = 0.5)) +
  theme(axis.title = element_text(family = windowsFont("Verdana"), color="black", size=12)) 

在得到Djork的建議后，我來到了下面的腳本，這個腳本有效，我很滿意。 我現在唯一要做的就是讓Legend成為一個整體（直方圖圖例和線條圖例組合成一個連貫的整體）。 有人有建議嗎？

# reformat data
set.seed(1)
df <- data.frame(runif(1000, 0, 200))
colnames(df) <- "Time_Diff"

bp_overall + 
  geom_histogram(data = subset(df, Time_Diff <= 12.5), aes(x = Time_Diff, fill="BAR BLUE"), binwidth = 5) + # subset for blue data, where aes fill is fill group 1 label
  geom_histogram(data = subset(df, Time_Diff > 12.5), aes(x = Time_Diff, fill="BAR TURQUOISE"), binwidth = 5) + # subset for turquoise data, where aes fill is fill group 2 label
  scale_fill_manual("Histogram Legend", values=c("blue", "paleturquoise2")) + # manually assign histogram fill colors
  geom_vline(aes(xintercept = 3, colour="LINE DARK BLUE"), linetype="twodash", size = 1) + # where aes colour is vline label
  scale_colour_manual("Line Legend", values="darkblue") + #removed legend title
  scale_x_continuous(breaks = seq(0, 202, 10)) +
  ggtitle("Time Difference")  +
  xlab("Time in Days") +
  ylab("Amount") +
  theme_light() +
  theme(panel.grid.minor = element_blank(),
        panel.border = element_blank(), 
        axis.line.x = element_line(size = 0.5, linetype = "solid", colour = "black"), 
        axis.line.y = element_line(size = 0.5, linetype = "solid", colour = "black"),
        legend.position = c(0.95, 0.95),
        legend.justification = c("right", "top"),
        legend.box.just = ("right"))

Answer 1

我認為@Jimbou的建議是可取的，但是通過為geom_histogram aes fill值和geom_vline aes colour值分配字符值，然后在scale_fill_manual或scale_colour_manual設置顏色， scale_fill_manual通過人工方式創建傳說。

然而，使用這種方法， aes fill只需要一個值（長度為1），因此您必須將df子集用於藍色和綠松石值，並為每個值繪制直方圖，其中截止值由您的binwidth決定。

這是方法。 請注意您的數據需要重新格式化。

# reformat data
set.seed(1)
df <- data.frame(runif(1000, 0, 200))
colnames(df) <- "Time_Diff"


bp_overall <- ggplot(data = df) 
bp_overall +
  geom_histogram(data = subset(df, Time_Diff <= 12.5), aes(x = Time_Diff, fill="BAR BLUE"), binwidth = 5) + # subset for blue data, where aes fill is fill group 1 label
  geom_histogram(data = subset(df, Time_Diff > 12.5), aes(x = Time_Diff, fill="BAR TURQUOISE"), binwidth = 5) + # subset for turquoise data, where aes fill is fill group 2 label
  scale_fill_manual("Histogram Legend", values=c("blue", "paleturquoise2")) + # manually assign histogram fill colors
  geom_vline(aes(xintercept = 3, colour="LINE DARK BLUE"), linetype="twodash", size = 1) + # where aes colour is vline label
  scale_colour_manual("Line Legend", values="darkblue") + # manually assign vline colors
  scale_x_continuous(breaks = seq(0, 202, 10)) +
  ggtitle("Time Difference")  +
  xlab("Time in Days") +
  ylab("Amount") +
  theme_light() +
  theme(panel.grid.minor = element_blank(),
    panel.border = element_blank(), 
    axis.line.x = element_line(size = 0.5, linetype = "solid", colour = "black"), 
    axis.line.y = element_line(size = 0.5, linetype = "solid", colour = "black"))

等等。添加你剩下的theme 。

編輯：回答有關如何統一圖例和減少兩個圖例類型之間的間距的問題

（1）拆下傳奇name通過設置V線，以“”中scale_fill_manual ，變化柱狀圖填充圖例name為“傳說中的” scale_colour_manual 。

（2）指定圖例應出現的order ，首先使用guides guide_legend填充然后填充顏色。

（3）通過設置拆下兩個圖例類型之間的y間隔legend.spacing.y到0 ，以及頂部和底部使用上去除邊緣legend.margin在theme

bp_overall <- ggplot(data = df) 
bp_overall +
  geom_histogram(data = subset(df, Time_Diff <= 12.5), aes(x = Time_Diff, fill="BAR BLUE"), binwidth = 5) + 
  geom_histogram(data = subset(df, Time_Diff > 12.5), aes(x = Time_Diff, fill="BAR TURQUOISE"), binwidth = 5) + 
  scale_fill_manual(name="Legend", values=c("blue", "paleturquoise2")) +
  geom_vline(aes(xintercept = 3, colour="LINE DARK BLUE"), linetype="twodash", size = 1) + 
  scale_colour_manual(name="", values="darkblue") + 
  scale_x_continuous(breaks = seq(0, 202, 10)) +
  ggtitle("Time Difference")  +
  xlab("Time in Days") +
  ylab("Amount") +
  theme_light() +
  theme(panel.grid.minor = element_blank(),
    panel.border = element_blank(),
    axis.line.x = element_line(size = 0.5, linetype = "solid", colour = "black"),
    axis.line.y = element_line(size = 0.5, linetype = "solid", colour = "black"),
    legend.spacing.y = unit(0, "cm"),
    legend.margin=margin(t=0, r=0.5, b=0, l=0.5, unit="cm")) +
  guides(fill = guide_legend(order = 1), 
     colour = guide_legend(order = 2))