如何在 R 中使用 ggplot2 创建具有连续比例的热图

Question

我有一个包含 1000 行的数据框，格式为

group = c("gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr3","gr3","gr3","gr3","gr3","gr3","gr3","gr3","gr3","gr3")
pos = c(1,2,3,4,5,6,7,8,9,10,1,2,3,4,5,6,7,8,9,10,1,2,3,4,5,6,7,8,9,10)
color = c(2,2,2,2,3,3,2,2,3,2,1,2,2,2,1,1,1,1,1,1,2,2,2,2,2,2,1,1,2,2)
df = data.frame(group, pos, color)

并且想制作一种热图，其中一个轴具有连续的比例（位置）。颜色列是分类的。但是由于我想使用分箱的大量数据点，即将它用作连续变量。

这或多或少的情节应该是这样的：

我想不出使用 ggplot2/R 创建这样一个情节的方法。我尝试了几种几何形状，例如geom_point()

ggplot(data=df, aes(x=strain, y=pos, color=color)) + 
  geom_point() +
  scale_colour_gradientn(colors=c("yellow", "black", "orange"))

提前感谢您的帮助。

Answer 1

这对您有帮助吗？

library(ggplot2)
group = c("gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr1","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr2","gr3","gr3","gr3","gr3","gr3","gr3","gr3","gr3","gr3","gr3")
pos = c(1,2,3,4,5,6,7,8,9,10,1,2,3,4,5,6,7,8,9,10,1,2,3,4,5,6,7,8,9,10)
color = c(2,2,2,2,3,3,2,2,3,2,1,2,2,2,1,1,1,1,1,1,2,2,2,2,2,2,1,1,2,2)
df = data.frame(group, pos, color)
ggplot(data = df, aes(x = group, y = pos)) + geom_tile(aes(fill = color)) 

看起来像这样

如果您喜欢，可以使用 3 种颜色渐变的改进版

library(scales)
ggplot(data = df, aes(x = group, y = pos)) + geom_tile(aes(fill = color))+ scale_fill_gradientn(colours=c("orange","black","yellow"),values=rescale(c(1, 2, 3)),guide="colorbar")