ggplot 条形图图例中的项目顺序出现问题

Question

我的数据看起来像

    language    tone        count   tone_percent    label_pos   pos
1   c           positive    3460    36.16977        18.08488    7
2   c           neutral     2046    21.38825        46.86389    7
3   c           negative    4060    42.44198        78.77901    7
4   c#          positive    3732    41.26949        20.63475    3
5   c#          neutral     1832    20.25876        51.39887    3
6   c#          negative    3479    38.47175        80.76413    3
7   c++         positive    3136    33.13960        16.56980    8
8   c++         neutral     2008    21.21949        43.74934    8
9   c++         negative    4319    45.64092        77.17954    8

我一直在尝试使用 ggplot2 条形图将它们可视化：

p <-ggplot() + theme_bw() + geom_bar(aes(y=tone_percent, x=reorder(language, -pos), fill=tone), data=data, stat="identity") + 
  geom_text(data=data, aes(x = language, y = label_pos, ymax=label_pos, hjust = 0.5, label = paste0(round(tone_percent),"%")), size=4) + 
  labs(x="Language", y="Percentage of tone") +
  scale_fill_manual(values=c('#F45E5A', '#5086FF', '#17B12B')) + 
  theme(legend.position="bottom", legend.direction="horizontal", legend.title = element_blank()) + coord_flip()

它给出了几乎完美的结果：

但是，图例按字母顺序显示标签，但我想以与图表中绘制条形相同的顺序显示它们：正，然后中性，然后负

有什么办法可以实现这一点吗？

Answer 1

您可以传递函数guides的参数，这将反转图例顺序，而无需重新排序条形。清理了一下：scaleguide_legend(reverse = TRUE)

ggplot(data, aes(x = reorder(language, -pos), y = tone_percent, fill = tone)) + 
    geom_col() + 
    geom_text(aes(y = label_pos, label = paste0(round(tone_percent),"%"))) + 
    coord_flip() + 
    labs(x = "Language", y = "Percentage of tone") +
    scale_fill_manual(NULL, values=c('#F45E5A', '#5086FF', '#17B12B'), 
                      guide = guide_legend(reverse = TRUE)) + 
    theme_bw() + 
    theme(legend.position = "bottom", 
          legend.direction = "horizontal")