Question

我有如下数据：

example.df <- as.data.frame(matrix( c("height","fruit",0.2,0.4,0.7,
                                      "height","veggies",0.3,0.6,0.8,
                                      "height","exercise",0.1,0.2,0.5,
                                      "bmi","fruit",0.2,0.4,0.6,
                                      "bmi","veggies",0.1,0.5,0.7,
                                      "bmi","exercise",0.4,0.7,0.8,
                                      "IQ","fruit",0.4,0.5,0.6,
                                      "IQ","veggies",0.3,0.5,0.7,
                                      "IQ","exercise",0.1,0.4,0.6), 
                                    nrow=9, ncol=5, byrow = TRUE))

colnames(example.df) <- c("phenotype","predictor","corr1","corr2","corr3")

因此3x3变量之间基本上具有三种不同的相关性。我想将相关性的增加可视化如下：

ggplot(example.df, aes(x=phenotype, y=corr1, yend=corr3, colour = predictor)) + 
  geom_linerange(aes(x = phenotype, 
                     ymin = corr1, ymax = corr3, 
                     colour = predictor), 
                  position = position_dodge(width = 0.5))+
  geom_point(size = 3,
             aes(x = phenotype, y = corr1, colour = predictor),
             position = position_dodge(width = 0.5), shape=4)+
  geom_point(size = 3, 
             aes(x = phenotype, y = corr2, colour = predictor),
             position = position_dodge(width = 0.5), shape=18)+
  geom_point(size = 3,
             aes(x = phenotype, y = corr3, colour = predictor),
             position = position_dodge(width = 0.5))+
  labs(x=NULL, y=NULL, 
       title="Stackoverflow Example Plot")+
  scale_colour_manual(name="", values=c("#4682B4", "#698B69", "#FF6347"))+
  theme_minimal()

这给了我以下情节：

问题：

用BMI和IQ避开geom_point形状的方式存在问题。它们都应该与颜色相同，如高度一样。
如何获得一个额外的图例，以显示圆形，十字形和正方形？（即在线上显示的三个不同的相关性：交叉=相关性1，正方形=相关性2，圆形=相关性3）。
图例现在显示一条线，一个圆，彼此交叉，而一条预测线（运动，水果，蔬菜）就足够了。

很抱歉，有多个问题，但是添加额外的图例（问题2）是最重要的，如果可以解决，我已经非常满意，剩下的就是奖金！：）

Answer 1

看看以下内容对您有用吗？主要思想是将geom_point层的数据帧从宽格式转换为长格式，并将映射相关性作为形状美感：

example.df %>%

  ggplot(aes(x = phenotype, color = predictor, group = predictor)) +
  geom_linerange(aes(ymin = corr1, ymax = corr3),
                 position = position_dodge(width = 0.5)) +
  geom_point(data = . %>% tidyr::gather(corr, value, -phenotype, -predictor),
             aes(y = value, shape = corr),
             size = 3,
             position = position_dodge(width = 0.5)) +
  scale_color_manual(values = c("#4682B4", "#698B69", "#FF6347")) +
  scale_shape_manual(values = c(4, 18, 16),
                     labels = paste("correlation", 1:3)) +
  labs(x = NULL, y = NULL, color = "", shape = "") +
  theme_minimal()

注意：颜色图例同时基于geom_linerange和geom_point，因此，图例键既包括线也包括点形状。尽管有可能摆脱第二个代码，但确实需要一些复杂的代码，因此，我认为绘图不会因此得到很大改善...

如何在ggplot2图中修改和添加额外的图例

1 个答案: