heatmap without ordering and dendrogram

r heatmap
EpiMan picture EpiMan · Sep 22, 2013 · Viewed 27.9k times · Source

I have a file with 2 columns and 1 million lines!! I only want to plot them without any ordering because I ordered the data. How can I make a heatmap with heatmap.2 without any dendrogram and reordering?

when I use 

heatmap.2(x, dendrogram="none")

Error: cannot allocate vector of size 4660.6 Gb

but

I tried without "Rowv" 

heatmap.2(x, Rowv=FALSE) 

Warning message:
In heatmap.2(x, Rowv = FALSE) :
  Discrepancy: Rowv is FALSE, while dendrogram is `column'. Omitting row dendogram.

Answer

nograpes picture nograpes · Sep 22, 2013

I think you have got both arguments there, you just have to put them together.

# Generate some sample data.
n<-1e6*2
m<-matrix(rnorm(n),ncol=2)
# Plot heatmap without reordering or dendrogram.
heatmap.2(m,dendrogram='none', Rowv=FALSE, Colv=FALSE,trace='none')

enter image description here

It is hard to imagine when it would be useful to plot so much data like this, but perhaps you have something in mind.

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