[R] how to get a row with its its p value below 0.01 ??

[Paul Hiemstra]

 ...in addition, I would definitely look at Bioconductor if you are
doing this kind of research.

Paul

On 09/14/2011 06:40 AM, Rolf Turner wrote:
> On 14/09/11 17:49, anand m t wrote:
>> Hi all,
>>
>> I'm analyzing micro array data.. it has produced a file (to be specific
>> matrix) withdimension of 35556 2.
>> first few lines of the matrix are as below..
>>
>> probe_name control.fdr.pvals.present
>> 10338001 0.000440001
>> 10338002 0.000583093
>> 10338003 0.000528449
>> 10338004 0.000610362
>> 10338005 0.000151825
>> 10338006 0.0001733
>> 10338007 0.000152924
>>
>> Now, i want only rows whose "control.fdr.pvals.present" values are below
>> 0.01.
>> How do i that?? Please help me soon...
>
> Your question indicates that your knowledge of R is very limited.
> If you are going to analyze micro array data in R, it behoves you
> to learn some R.  Read, mark, and inwardly digest ``An Introduction
> to R'' (under "Manuals" on the R web page, www.r-project.org).
> At the very least.
>
> To answer your question:  If your matrix is named "m" then
>
>     m[m[,2] <= 0.01,]
>
> gives you what you want.  Possibly more perspicuously:
>
>     ind <- m[,2] <= 0.01 # ind is a logical vector of length = nrow(m)
>     m[ind,] # This selects those rows of m where ind is TRUE
>
>     cheers,
>
>         Rolf Turner
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.


-- 
Paul Hiemstra, Ph.D.
Global Climate Division
Royal Netherlands Meteorological Institute (KNMI)
Wilhelminalaan 10 | 3732 GK | De Bilt | Kamer B 3.39
P.O. Box 201 | 3730 AE | De Bilt
tel: +31 30 2206 494

http://intamap.geo.uu.nl/~paul
http://nl.linkedin.com/pub/paul-hiemstra/20/30b/770