强制错误栏位于栏的中间 [英] Force error bars to be in the middle of bar

问题描述

我使用R和ggplot2来绘制带有误差线的漂亮的基本条形图，但是我遇到了麻烦，迫使它们在我创建的线条的中心。

我的代码如下：

  library（ggplot2）$ （b）b 
 
类型<-c（A，A，A，B，B，B）
时间< -  c （0,24,48,0,24,48）
 CellCount <-c（321,213,123,432,234,324）
 Error -c（12,32,12,34,23,21）$ b $ （df，aes（x = Time，y = CellCount，fill = Type））+ $ b（df，aes $ b geom_bar（stat =identity，position =dodge）+ 
 xlab（Time（h））+ ylab（Cell count）+ 
 scale_x_continuous（breaks = seq（0 ，48,24））+ 
 scale_fill_discrete（labels = c（Anirridia，Control））+ 
 guides（fill = guide_legend（title = NULL））
 
p + geom_errorbar（aes（ymin = CellCount  -  Error，
 ymax = CellCount + Error），
 width = 0.9，
 position =dodge）
  
 
 
 
但是，这会产生以下图表：  $ b 
  
 
 
 
错误栏位于栏的边缘。我认为这是因为他们在0,24和48小时的时间内被绘制出来，但我不知道如何将他们移动到每个栏的中心 
 
 
请告诉我如何移动错误栏
 
 
 
预先感谢 
 
 
编辑：我以前看到这个链接的问题是重复的，但是当我添加 
 
 
  p + geom_errorbar（aes（ymin = CellCount - 错误，
 ymax = CellCount + Error），
 width = 0.9，
 position = position_dodge（.9））
  
我仍然得到和以前一样的情节
 
 
 
 Edit2：我认为Rstudio可能存在问题？或者至少在我的安装中...因为我复制的代码粘贴在重复的问题中，我得到了下图： http://imgur.com/H2DRvqg  
解决方案
虽然@ jeremycg的回答是正确的（+ 1为ggplot主题系统的晦涩知识），它更多的是一个副作用比解决方案。
 
 
 
让我们想一下典型的用例情景条形图。通常，我们会在试图呈现数据时使用条形图： b 
 $ b 
 
 
连续离散
 
 
 
 
 
现在，我们有以下数据： 
 
 
 
 / li> 
 
 
 
 
对于这种数据类型，点图更为合适。但我们可以看到它看起来有点荒谬，因为我们的数据并不是真正连续的。
  ggplot（df，aes（Time， CellCount，color = Type））+ 
 geom_point（stat =identity）+ 
 geom_errorbar（aes（
 ymin = CellCount  -  Error，
 ymax = CellCount + Error）， 
 width = 0.9）
  
对于这种性质的表示，应该使用分类变量为它们的x坐标。  
 
 
这可以通过预先处理变量Time作为一个因子或通过在美学字符串中调用变量as.factor来完成（ aes ）。
  ggplot（df，aes（
x = as.factor时间），＃as.factor（）使得它成为离散比例
y = CellCount，
 fill = Type））+ 
 geom_bar（stat =identity，position =dodge）+ 
 geom_errorbar（aes（
 ymin = CellCount  -  Error，
 ymax = CellCount + Error），
 width = 0.9，
 position = position_dodge（width = 0.9）） +＃现在你可以使用它
 labs（x =Time（h），y =Cell count）+ 
 scale_fill_discrete（labels = c（Anirridia，Control））
  
 
I'm using R and ggplot2 to plot a pretty basic bar graph with error bars, but I'm having trouble forcing them to be in the center of the bars that I create. 


My code is the following:
library(ggplot2)


Type <- c("A", "A", "A", "B", "B", "B")
Time <- c(0, 24, 48, 0, 24, 48)
CellCount <- c(321,213,123,432,234,324)
Error <- c(12,32,12,34,23,21)
df <- data.frame(Type,Time,CellCount,Error)

p <- ggplot(df, aes(x=Time, y = CellCount, fill = Type)) + 
     geom_bar(stat = "identity", position = "dodge") + 
     xlab("Time (h)") + ylab("Cell count") + 
     scale_x_continuous(breaks = seq(0,48,24)) +
     scale_fill_discrete(labels = c("Anirridia", "Control")) + 
     guides(fill = guide_legend(title = NULL))

p + geom_errorbar(aes(ymin = CellCount - Error, 
                      ymax = CellCount + Error), 
                      width = 0.9, 
                      position = "dodge")
But this produces the following plot:



The error bars are at the edges of the bars. I think it´s because they are being plotted at 0, 24 and 48 hours of time, but I don't know how to move them to the center of each bar

Please suggest me how can I "move" the error bars

Thanks in advance

Edit: I previously saw the question that has been linked for this one as duplicate, but when I add 
 p + geom_errorbar(aes(ymin = CellCount - Error, 
                  ymax = CellCount + Error), 
                  width = 0.9, 
                  position=position_dodge(.9))
I'm still getting the same plot as before 

Edit2: I think there's an issue with Rstudio maybe? Or at least with my installation... Because I´ve copy pasted the code in the "duplicate" question and I get the following graph... http://imgur.com/H2DRvqg
解决方案
While @jeremycg's answer is correct (+1 for obscure knowledge of ggplot theme system), it's more of a side-effect than a solution.

Let's just think for a moment of the typical use case scenario for a bar chart. Generally we would use a bar chart when we are trying to present data that are:


Discrete by Continuous


Right now, we have data that are:


Continuous by Continuous


A dot plot would be more appropriate for this data type. But we can see that it looks a bit ridiculous because our data are not truly continuous.
ggplot(df, aes(Time,CellCount, color = Type)) + 
  geom_point(stat="identity") + 
  geom_errorbar(aes(
    ymin = CellCount - Error, 
    ymax = CellCount + Error),   
    width = 0.9)
For a presentation of this nature, one ought to use a categorical variable for their x-coordinate. 

This can be accomplished by pre-processing your variable, Time, as a factor, or by calling the variable as.factor in the aesthetic string (aes).
ggplot(df, aes(
    x=as.factor(Time), # as.factor() makes this a discrete scale
    y = CellCount, 
    fill = Type)) +
  geom_bar(stat = "identity", position = "dodge") +
  geom_errorbar(aes(
    ymin = CellCount - Error, 
    ymax = CellCount + Error),   
    width = 0.9, 
    position = position_dodge(width = 0.9)) + # now you can use it
  labs(x= "Time (h)", y = "Cell count") +
  scale_fill_discrete(labels = c("Anirridia", "Control")) 


                        
这篇关于强制错误栏位于栏的中间的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！