[R] wrong data interpretation in R

jim holtman jholtman at gmail.com
Mon Nov 26 18:15:39 CET 2012


Also when reading a CSV file, if you do not want characters columns
converted to factors, use 'as.is = TRUE' as one of the parameters.  If
you have a column that is a factor, to convert it to numeric you have
to do the following:

as.numeric(as.character(factorColumn))

notice that you have to convert it to character first; otherwise you
will get the numeric value of the factor which is probably not what
you want.

On Mon, Nov 26, 2012 at 12:02 PM, Sarah Goslee <sarah.goslee at gmail.com> wrote:
> Most likely there's something amiss in your csv file: R won't convert
> numeric data to factors unless there are non-numeric characters
> included.
>
> First check your csv file for errors. If that doesn't solve your
> problem, please provide a reproducible example.
> http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example
>
> Sarah
>
> On Mon, Nov 26, 2012 at 10:59 AM, EcoFranc <robrit at gmx.de> wrote:
>> Hi,
>>
>> maybe somebody would be kind enough to help a bloody and unprofessional
>> beginner like me (and I hope I did not overlook the answer to my question on
>> the website). I've imported a csv data frame into R, but I can't run a
>> regression because R interprets 4 out of 5 variables as factors (rather than
>> numeric vectors). I tried the as.numeric() command, but R says it is invalid
>> to change the storage mode of a factor. Is there any way to change the mode
>> of a factor into numeric.
>>
>> I am very grateful for help. Thank you very much, Robert.
>>
>>
>
>
> --
> Sarah Goslee
> http://www.functionaldiversity.org
>
> ______________________________________________
> 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.



-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.




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