[R] simple generation of artificial data with defined features

[Christoph Meyer]

Hi,

to add voter.id and election.year to your data frame you could try:

el.dt.exp$voter.id=seq(1:nrow(el.dt.exp))

el.dt.exp$election.year=2005

Cheers,

Christoph Meyer


***************************************************************
Dr. Christoph Meyer
Institute of Experimental Ecology
University of Ulm
Albert-Einstein-Allee 11
D-89069 Ulm
Germany
Phone:  ++49-(0)731-502-2675
Fax:    ++49-(0)731-502-2683
Mobile: ++49-(0)1577-156-7049
E-mail: christoph.meyer at uni-ulm.de
http://www.uni-ulm.de/index.php?id=7885
***************************************************************

Saturday, August 23, 2008, 1:25:05 PM, you wrote:

> Dear Mr. Christos Hatzis,

> thank you so much for your answer which is in my eyes just brilliant! I
> followed it step by step (great and detailed explanation) and nearly
> everything is fine. - Except a problem in the very end, I haven't found
> a solution for until now. (Despite playing arround quite a lot...)
> Please let me explain:

>> election.2005 <- c(16194,13136,3494,3838,4648,4118) #cut of last 3
> digits, cause my laptop can't handle millions of rows...
>> attr(election.2005, "class") <- "table"
>> attr(election.2005, "dim") <- c(1,6)
>> attr(election.2005, "dimnames") <- list(c("votes"), c("spd", "cdu",
> "csu", "gruene", "fdp", "pds"))
>> head(election.2005)
>         spd   cdu  csu gruene  fdp  pds
> votes 16194 13136 3494   3838 4648 4118
>> el.dt <- as.data.frame(election.2005)
>> el.dt.exp <- el.dt[rep(1:nrow(el.dt), el.dt$Freq), -ncol(el.dt)]
>> dim(el.dt.exp)
> [1] 45428     2
>> head(el.dt.exp)
>      Var1 Var2
> 1   votes  spd
> 1.1 votes  spd
> 1.2 votes  spd
> 1.3 votes  spd
> 1.4 votes  spd
> 1.5 votes  spd

> My problem now is, that I would need either an autoincrementing
> identifier instead of "votes" in Var1 or the possibility to access the
> numbering by a column name (i.e. Var0). In addition I need a 3rd
> Variable for the year oft the election (2005, which is the same for all,
> but needed later on). So this is what it should look like:

>      voter.id     party     election.year
> 1       1        spd            2005
> 1.1     2         spd          2005
> 1.2     3        spd           2005
> 1.3     4        spd            2005
> 1.4     5        spd            2005
> 1.5     6        spd            2005

...