[R] heatmap color distribution

[Ruben Roa]

> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of Jacob Michaelson
> Sent: 21 July 2005 12:26
> To: r-help at stat.math.ethz.ch
> Subject: [R] heatmap color distribution
> 
> 
> Hi all,
> 
> I've got a set of gene expression data, and I'm plotting several  
> heatmaps for subsets of the whole set.  I'd like the heatmaps 
> to have  the same color distribution, so that comparisons may be made  
> (roughly) across heatmaps; this would require that the color  
> distribution and distance functions be based on the entire dataset,  
> rather than on individual subsets.  Does anyone know how to do this?
> 
> Thanks in advance,

For each heatmap, in image() set the zlim argument to c(zmin,zmax) where 
zmin and zmax are the minimum and maximum observed across the entire data 
set. Also, for each heatmap set col=heat.colors(n) to the same n for all 
heatmaps. I do that with image.kriging in geoR. Hope it works for you.
Ruben