[R] Presence/ absence data from matrix to single column

[Rui Barradas]

Hello,

If all your species have different names, you can allways try one of
1. if the non-species follow a pattern, negate those columns and you'll 
have the species columns.
2. are the species the last columns? Use positional referencing.

Rui Barradas
Em 08-10-2012 00:16, Andrea Goijman escreveu:
> Ill try this one as well.
>
> And I guess the one below is not going  to work, because all my species
> have different names.
>
> Thanks!
>
> #nms <- names(adat)
> nms <- c("Year", "Route", "Point", paste0("Sp", 1:250))
>
> pattern <- "^Sp[[:digit:]]+$"
> whichCols <- grep(pattern, nms)
> whichNames <- nms[whichCols]
>
> reshape(..., varying = whichCols, times = whichNames, ...)
> On Sun, Oct 7, 2012 at 3:02 PM, arun <smartpink111 at yahoo.com> wrote:
>
>> Hi,
>> I guess you are not talking about the melt() method.
>> dat1<-read.table(text="
>> Year    Route    Point    Sp1    Sp2    Sp3
>> 2004    123    123-1    0    1    0
>> 2004    123    123-2    0    1    1
>> 2004    123    123-10    1    1    0
>> ",header=TRUE,sep="",stringsAsFactors=FALSE)
>>
>>
>> #If all the Sp columns are located next to another as shown in your
>> example dataset, then you can also try this:
>> name1<-unlist(strsplit(paste(colnames(dat1)[4:6],collapse=" ")," "))
>> reshape(dat1,varying=4:6,v.name
>> ="Sp-value",times=name1,timevar="Sp-name",idvar=c("Year","Route","Point"),direction="long")
>>
>> A.K.
>>
>>
>>
>>
>>
>>
>> ----- Original Message -----
>> From: Rui Barradas <ruipbarradas at sapo.pt>
>> To: agoijman <agoijman at cnia.inta.gov.ar>
>> Cc: r-help at r-project.org
>> Sent: Sunday, October 7, 2012 2:32 PM
>> Subject: Re: [R] Presence/ absence data from matrix to single column
>>
>> Hello,
>>
>> I haven't been following this thread but apparently the answer to your
>> worries is no.
>> You can use a combination of names() and grep() to sort it out.
>> something like
>>
>> #nms <- names(adat)
>> nms <- c("Year", "Route", "Point", paste0("Sp", 1:250))
>>
>> pattern <- "^Sp[[:digit:]]+$"
>> whichCols <- grep(pattern, nms)
>> whichNames <- nms[whichCols]
>>
>> reshape(..., varying = whichCols, times = whichNames, ...)
>>
>>
>> Hope this helps,
>>
>> Rui Barradas
>> Em 07-10-2012 15:35, agoijman escreveu:
>>> The problem with that, is that I just wrote an example of my database,
>> but I
>>> have around 250 species and more than 500 sites. In the approach you show
>>> me, it looks like I have to enter every species name and sites
>> individually,
>>> right?
>>>
>>>
>>>
>>> --
>>> View this message in context:
>> http://r.789695.n4.nabble.com/Presence-absence-data-from-matrix-to-single-column-tp4645271p4645331.html
>>> Sent from the R help mailing list archive at Nabble.com.
>>>
>>> ______________________________________________
>>> 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.
>> ______________________________________________
>> 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.
>>
>>
>