r - ggbiplot - 改变点的大小

Question

有人知道如何更改点大小并仍然保持下面代码中的组颜色吗？

只需添加 geom_point(size = 8) 即可将所有点的颜色更改为黑色。

代码:

library(ggbiplot)
data(wine)
wine.pca <- prcomp(wine, scale. = TRUE)
g <- ggbiplot(wine.pca, obs.scale = 1, var.scale = 1, 
              groups = wine.class, varname.size = 8, labels.size=10  , ellipse = TRUE, circle = TRUE)
g <- g + scale_color_discrete(name = '') #+  geom_point(size = 8)
g <- g + opts(legend.direction = 'horizontal', 
              legend.position = 'top')
print(g)

Answer 1

在 geom_point 中添加颜色美学将保持按组着色的点。另外，我将 opts 更改为 theme，因为 opts 已被弃用。

ggbiplot(wine.pca, obs.scale = 1, var.scale = 1, group=wine.class,
              varname.size = 8, labels.size=10, 
              ellipse = TRUE, circle = TRUE) +
  scale_color_discrete(name = '') +  
  geom_point(aes(colour=wine.class), size = 8) +
  theme(legend.direction ='horizontal', 
        legend.position = 'top')