r - ggplot2中直方图的颜色

Question

我正在按以下方式绘制数据框的直方图，但我想将颜色设置为蓝色/其他任何颜色。但是当我放置 color = "blue" 时，它不会改变颜色并在旁边添加额外的组。

> str(neg.all.frame)
'data.frame':   455634 obs. of  2 variables:
 $ probability: num  0.645 0.536 0.365 0.523 0.587 ...
 $ group      : chr  "Unknown/Negative" "Unknown/Negative" "Unknown/Negative" "Unknown/Negative" ...

ggplot(neg.all.frame, aes(colour = "blue", probability, fill = group)) + geom_histogram(alpha = 0.2) +
  xlab("Probability of Being Interested in Fashion") + ylab("Number of People")

我该如何解决？

Answer 1

您将字符串 "blue" 作为美学映射传递。您需要做的是使用 fill=blue 作为 geom_histogram 中的参数。试试这个:

ggplot(neg.all.frame, aes(probability, fill = group)) +    
 geom_histogram(alpha = 0.2, fill = "blue") + 
 xlab("Probability of Being Interested in Fashion") + 
 ylab("Number of People")

在图形语法中，美学映射将数据映射到可视化的美学特征。您要做的不是映射，而是颜色的静态变化。