Place the Y axis to the left of the heatmap?

Question

How to make a heatmap with Y axis labels on the left? It seems that by default it is right. Do I need to create a custom axis using axis() ?

Answer 1

In the heatmap function, the heatmap positions are hardcoded. But it would be very easy to change only one number to place it on the other side. Type “Heatmap” on the console and change the first argument from 4 to 2 in the second axis() call.

All that I changed was:

 axis(2, iy, labels = labRow, las = 2, line = -0.5, tick = 0, # the 2 used to be 4 cex.axis = cexRow) 

It is still necessary to make changes to the fields for the switch. Changing the current value from 0 to 5 seemed to create enough space in the example in which I was playing from the help page:

 ... par(mar = c(margins[1L], 5, 0, margins[2L])) 

This was my test case:

 x <- as.matrix(mtcars) rc <- rainbow(nrow(x), start=0, end=.3) cc <- rainbow(ncol(x), start=0, end=.3) utils::str(hv) # the two re-ordering index vectors ## no dendrogram (nor color strip) heatmap.new(x, Colv = NA, Rowv=NA, col = cm.colors(256), scale="column", margins=c(5,2), xlab = "specification variables", ylab= "Car Models", main = "heatmap(<Mtcars data>, ..., scale = \"column\")")