[R] Multiple Ploting Colors

[Steve Lianoglou]

One more thing:

On Mon, Jul 12, 2010 at 12:55 PM, Steve Lianoglou
<mailinglist.honeypot at gmail.com> wrote:
> Hi,
>
> On Mon, Jul 12, 2010 at 12:02 PM, Richardson, Patrick
> <Patrick.Richardson at vai.org> wrote:
>> I'm trying to use multiple plotting colors in my code. My first "ifelse" statement successfully does what I want. However, now I want anything less than -4.5 to be green and the rest black. I want another "col" argument but can only use one. How could I go about getting separate colors for anything above 4.5  and less than -4.5?
>>
>> plot(three, type="h", col=ifelse(three > 4.5, "red", "black"), xlim=c(0,500), ylim=range(three), lwd=2,
>>     xlab="Chromosome", ylab="Z-Score", font.lab=2, font=2, main="Upregulated Genes in Patient Sample")
>
> How about:
>
> my.colors <- ifelse(three > 4.5, "red", "black")
> my.colors[three < -4.5] <- 'green'
>
> plot(three, type='h', col=my.colors, ...)

Depending on what you want the plot for, perhaps you might consider
changing your color palette from green -> black -> red to something
like blue -> black -> yellow, since many folks who are color can not
differentiate green from red all that well.

-- 
Steve Lianoglou
Graduate Student: Computational Systems Biology
 | Memorial Sloan-Kettering Cancer Center
 | Weill Medical College of Cornell University
Contact Info: http://cbio.mskcc.org/~lianos/contact