Hello,
can anybody help me with this problem?
I have a dataframe, which contains its values as factors though I have numbers
but it was read as factors with "scan". Now I would like to convert
these
columns (multiple) to a numeric format.
# this example creates a similar situation
testdata <- as.factor(c("1.1",NA,"2.3","5.5"))
testdata2 <-
as.factor(c("1.7","4.3","8.5",10.0))
df <- data.frame(testdata, testdata2)
what do I have to do to get the same datafram but with numeric values???
Antje
try this (also look at R-FAQ 7.10):
sapply(df, function (x) as.numeric(levels(x))[as.integer(x)])
I hope it helps.
Best,
Dimitris
----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven
Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
http://www.student.kuleuven.be/~m0390867/dimitris.htm
----- Original Message -----
From: "Antje" <niederlein-rstat at yahoo.de>
To: <r-help at stat.math.ethz.ch>
Sent: Tuesday, December 04, 2007 11:46 AM
Subject: [R] Dataframe manipulation
> Hello,
>
> can anybody help me with this problem?
> I have a dataframe, which contains its values as factors though I
> have numbers
> but it was read as factors with "scan". Now I would like to
convert
> these
> columns (multiple) to a numeric format.
>
>
> # this example creates a similar situation
>
> testdata <-
as.factor(c("1.1",NA,"2.3","5.5"))
> testdata2 <-
as.factor(c("1.7","4.3","8.5",10.0))
>
> df <- data.frame(testdata, testdata2)
>
> what do I have to do to get the same datafram but with numeric
> values???
>
> Antje
>
> ______________________________________________
> 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.
>
Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
See R-FAQ # 7-11 for the solution. Have a look at http://finzi.psych.upenn.edu/R/Rhelp02a/archive/98227.html for a discussion of this type of problem and ways to get around the issue. --- Antje <niederlein-rstat at yahoo.de> wrote:> Hello, > > can anybody help me with this problem? > I have a dataframe, which contains its values as > factors though I have numbers > but it was read as factors with "scan". Now I would > like to convert these > columns (multiple) to a numeric format. > > > # this example creates a similar situation > > testdata <- as.factor(c("1.1",NA,"2.3","5.5")) > testdata2 <- as.factor(c("1.7","4.3","8.5",10.0)) > > df <- data.frame(testdata, testdata2) > > what do I have to do to get the same datafram but > with numeric values??? > > Antje > > ______________________________________________ > 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. >