基于数据帧列的Y轴ggplot盒图

Question

我用ggplot创建了盒子图，但是我想根据我使用汇总统计创建的不同数据框中列的顺序来更改y轴的顺序。

这是脚本。脚本下面是对我所需输出的描述。

#data 
df <- data.frame(City = c("NY", "AMS", "BER", "PAR", "NY", "AMS", "AMS", "PAE"), 
      Time_Diff = c(4, 2, 7, 9, 2, 1, 10, 9), 
      Outliers = c(0, 0, 0, 0, 0, 1, 1, 0)) 

#data summary 
summary <- df %>% 
     group_by(City) %>% 
     summarise(Median = median(Time_Diff), 
     IQR = IQR(Time_Diff), 
     Outliers = sum(Outliers)) %>% 
     arrange(desc(Median), desc(IQR), desc(Outliers)) 

summary <- as.data.frame(summary) 


# Create ggplot object 
bp <-ggplot(data = df, aes(x = reorder(City, Time_Diff, FUN = median), y= Time_Diff)) # Creates boxplots 

# Create boxplot figure 
bp + 
    geom_boxplot(outlier.shape = NA) + #exclude outliers to increase visibility of graph 
    coord_flip(ylim = c(0, 25)) + 
    geom_hline(yintercept = 4) + 
    ggtitle("Time Difference") + 
    ylab("Time Difference") + 
    xlab("City") + 
    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 

我想是y轴（翻转的x轴）的顺序是相同的，如发明内容数据帧City列的顺序。这意味着：

从上到下：PAE，PAR，BER，NY，AMS

任何有效的和优雅的建议？

SOLUTION

谢谢Prradep，我用您的解决方案的脚本和它的作品。我稍微调整了它，这样我就不必再次键入轴的值。我重新使用了数据框中的城市矢量。这是我使用的脚本：

#data 
df <- data.frame(City = c("NY", "AMS", "BER", "PAR", "NY", "AMS", "AMS", "PAE"), 
      Time_Diff = c(4, 2, 7, 9, 2, 1, 10, 9), 
      Outliers = c(0, 0, 0, 0, 0, 1, 1, 0)) 

#data summary 
summary <- df %>% 
    group_by(City) %>% 
    summarise(Median = median(Time_Diff), 
     IQR = IQR(Time_Diff), 
     Outliers = sum(Outliers)) %>% 
    arrange(desc(Median), desc(IQR), desc(Outliers)) 

summary <- as.data.frame(summary) 

# Preproces data for figure 
order_city <- summary$City 

# Create ggplot object 
bp <-ggplot(data = df, aes(x = reorder(City, Time_Diff, FUN = median), y= Time_Diff)) # Creates boxplots 

# Create boxplot figure 
bp + 
    geom_boxplot(outlier.shape = NA) + #exclude outliers to increase visibility of graph 
    coord_flip(ylim = c(0, 25)) + 
    geom_hline(yintercept = 4) + 
    ggtitle("Time Difference") + 
    ylab("Time Difference") + 
    xlab("City") + 
    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 
    scale_x_discrete(limits = rev(order_city)) #this is the function to change the order of the axis 

Answer 1

添加scale_x_discrete(limits = rev(c('PAE', 'PAR', 'BER', 'NY', 'AMS')))会做诡计。

---

这是你在找什么：

# Create ggplot object 
bp <-ggplot(data = df, aes(x = reorder(City, Time_Diff, FUN = median), y= Time_Diff)) # Creates boxplots 

# Create boxplot figure 
bp + 
    geom_boxplot(outlier.shape = NA) + #exclude outliers to increase visibility of graph 
    coord_flip(ylim = c(0, 25)) + 
    geom_hline(yintercept = 4) + 
    ggtitle("Time Difference") + 
    ylab("Time Difference") + 
    xlab("City") + 
    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 
    scale_x_discrete(limits = rev(c('PAE', 'PAR', 'BER', 'NY', 'AMS')))