R help - Nov 2009 - heatmap.2 adapting the colour scale and text overlay

Hello,

I am using heatmap.2 from the gplots library to plot a small symmetrical 
matrix.

This is the command:

heatmap.2(tempHeat,symm=T,trace="none",cexRow=0.7,cexCol=0.7,col="redgreen",density.info="none")

I have a couple of questions:
1) The range is from -0.2 to 0.4 and the colour scheme I am using is 
redgreen.  What I would like is that a zero value to be black, 0.4 
strong green and -0.2 red.  Is this possible?  At the moment around 0.1 
is black.
2) Is it possible to overlay text on the squares of colour?  How ould 
one go about doing that.

I am happy to use another heatmap function if ti would be better.  I am 
not using the original heatmap as it does not provide a colour key.

Thanks

Dan
-- 
**************************************************************
Daniel Brewer, Ph.D.

Institute of Cancer Research
Molecular Carcinogenesis
Email: daniel.brewer at icr.ac.uk
**************************************************************

The Institute of Cancer Research: Royal Cancer Hospital, a charitable Company
Limited by Guarantee, Registered in England under Company No. 534147 with its
Registered Office at 123 Old Brompton Road, London SW7 3RP.

This e-mail message is confidential and for use by the a...{{dropped:2}}

On Nov 23, 2009, at 10:02 AM, Daniel Brewer wrote:
> Hello,
>
> I am using heatmap.2 from the gplots library to plot a small  
> symmetrical matrix.
>
> This is the command:
>
> heatmap. 
> 2 
> (tempHeat 
> ,symm 
> = 
> T 
> ,trace 
>
="none",cexRow=0.7,cexCol=0.7,col="redgreen",density.info="none")
>
> I have a couple of questions:
> 1) The range is from -0.2 to 0.4 and the colour scheme I am using is  
> redgreen.  What I would like is that a zero value to be black, 0.4  
> strong green and -0.2 red.  Is this possible?  At the moment around  
> 0.1 is black.
Perhaps:
color.palette = colorRampPalette(c("green", "black",
"pink", "red"))
  heatmap.2(tempHeat,symm=T,trace="none",cexRow=0.7,cexCol=0.7,  
col=color.palette, density.info="none")
> 2) Is it possible to overlay text on the squares of colour?  How  
> ould one go about doing that.
>
> I am happy to use another heatmap function if ti would be better.  I  
> am not using the original heatmap as it does not provide a colour key.
>
> Thanks
>
> Dan
> -- 
> **************************************************************
> Daniel Brewer, Ph.D.
>
> Institute of Cancer Research
> Molecular Carcinogenesis
> Email: daniel.brewer at icr.ac.uk
> **************************************************************
>
> The Institute of Cancer Research: Royal Cancer Hospital, a  
> charitable Company Limited by Guarantee, Registered in England under  
> Company No. 534147 with its Registered Office at 123 Old Brompton  
> Road, London SW7 3RP.
>
> This e-mail message is confidential and for use by the a...{{dropped: 
> 2}}
>
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