[BioC] color scheme heatmap.2

[Roel Verhaak]

Dear list,

I am generating genes vs samples expression heatmaps using the heatmap.2 
function from the gplots library. The heatmap data is centered around 
zero and varies from approximately -6 to 6.

Like the heatmap function, a color scheme needs to be specified, for 
which I have used greenred(75) so far.  The most extreme green and red 
colors are now assigned to the most extreme values; it is also possible 
to define a color scheme that assigns the most extreme colors to not the 
most extreme values, for instance -3 and 3 in my case?

Thanks and regards,
Roel Verhaak