如何在R中使用ggplot2创建具有连续比例的热图

Question

我有一个包含几千行的数据框，形式为

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。 但是由于大量的数据点，我想使用装箱，即将其用作连续变量。

这大致相当于情节的样子：

我想不出一种使用ggplot2 / R创建这样的图的方法。 我尝试了几种几何，例如geom_point（）

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

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

如果您愿意，可提供带有3种颜色渐变的改进版本

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")