如何在R的热图中添加水平分隔符

Question

使用以下代码：

library(gplots)
heatmap.2(as.matrix(mtcars),density.info="none",trace="none",Colv=FALSE,Rowv=FALSE,dendrogram="none",margin=c(10,10))

我可以创建热图。但我想要做的是添加给定块的水平分隔符：

假设我有3个块定义为列表：

block1 <- c("Mazda RX4","Mazda RX4 Wag","Datsun 710","Hornet 4 Drive","Hornet Sportabout","Valiant","Duster 360","Merc 240D")
block2 <- c("Merc 230","Merc 280","Merc 280C","Merc 450SE","Merc 450SL","Merc 450SLC","Cadillac Fleetwood", "Lincoln Continental","Chrysler Imperial"  ,"Fiat 128","Honda Civic","Toyota Corolla","Toyota Corona","Dodge Challenger","AMC Javelin")
block3 <- c("Camaro Z28","Pontiac Firebird","Fiat X1-9","Porsche 914-2","Lotus Europa","Ford Pantera L","Ferrari Dino","Maserati Bora","Volvo 142E")

Answer 1

您可以在rowsep函数中使用参数heatmap.2（类似地，如果您对添加垂直线感兴趣，可以使用参数colsep）。

在这里，您希望在第8个值之后放置分隔，然后在第23个之后放置分离，以便您可以执行以下操作：

heatmap.2(as.matrix(mtcars),
          density.info="none", 
          trace="none", 
          Colv=FALSE, 
          Rowv=FALSE, 
          dendrogram="none", 
          margin=c(10,10),
          # now the separations:
          rowsep=c(8, 23))

NB：根据block向量检索水平线的位置，你可以做到

which(row.names(mtcars)==block1[length(block1)]) # 8
which(row.names(mtcars)==block2[length(block2)]) # 23