如何使用ggplot2自定义点图图例的内容

Question

我正在使用这个表：

fruit   value   feature Ratio
tomato  1.79614067223751    length  0.00983606557377
zucchini    3.03886853214095    size    0.034188034188034
tomato  1.64545172419968    size    0.013114754098361
potato  4.25443807208955    size    0.008383233532934
zucchini    5   colour  0.051282051282051
potato  1.46068422675856    magic   0.004790419161677
potato  5   flavour 0.011377245508982
tomato  4.86348870541553    flavour 0.026229508196721
zucchini    2.89808116631958    flavour 0.034188034188034

要生成此点图，

Dotplot <- read.delim("test.txt", header = TRUE)

ggplot(Dotplot,aes(factor(fruit),feature)) + 
        geom_point(aes(colour=value,size=Ratio)) + 
        scale_colour_gradient(low="red", high="blue") + 
        scale_size(range=c(1,10)) + theme_bw() + 
        theme(axis.text=element_text(size=10), 
              axis.title=element_text(size=10,face="bold")) + 
        theme(axis.text.x = element_text(size = 12, angle = 90))

我想要的是自定义"Ratio“图例，并将点的数量加倍，以显示非常小的点的偶数值。这有可能吗？

提前感谢

Answer 1

您可以设置比例图例中显示的点数以及使用"breaks“参数表示的值：

scale_size(range=c(1,10), breaks = seq(0.01, 0.05, 0.005))

绘图代码：

ggplot(Dotplot,aes(factor(fruit),feature)) + 
  geom_point(aes(colour=value,size=Ratio)) + 
  scale_colour_gradient(low="red", high="blue") + 
  scale_size(range=c(1,10), breaks = seq(0.01, 0.05, 0.005)) + theme_bw() + 
  theme(axis.text=element_text(size=10), 
        axis.title=element_text(size=10,face="bold")) + 
  theme(axis.text.x = element_text(size = 12, angle = 90))

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