[R] data manipulation docs

[Frank E Harrell Jr]

Federico Calboli wrote:
> Hi All,
> 
> Is there some document/manual about data manipulation within R that I 
> could use as a reference (obviously, aside the R manuals)?
> 
> The reason I am asking is that I have a number of data frames/matrices 
> containg genetic data. The data is in a character form, as in:
> 
>    V1 V2 V3 V4 V5
> 1 AA AG AA GG AG
> 2 AC AA AA GG AG
> 3 AA AG AA GG AG
> 4 AA AA AA GG AG
> 5 AA AA AA GG AA
> 
> I need, to chop, subset, and variously manipulate this kind of data, 
> sometimes keeping the data in its character format, sometimes converting 
> it to numeric form (i.e. substitute each data point with the equivalent 
> factor value). Since the data is ofthe quite big, I have to keep things 
> memory efficient.
> 
> This whole game is getting excedingly time consuming and frustrating, 
> because I end up with random pieces of code that I save, patching a 
> particular problem, but difficult to be 'abstracted' for a new task, so 
> I get back close to square one annoyingly often.
> 
> Cheers,
> 
> Federico Calboli
> 
> 

There is a large data manipulation section on the Alzola Harrell 
document available on CRAN under contributed docs, or a slightly more up 
to date version at biostat.mc.vanderbilt.edu

-- 
Frank E Harrell Jr   Professor and Chair           School of Medicine
                      Department of Biostatistics   Vanderbilt University