[R] Odp: converting factor to numeric gives "NAs introduced by coercion"

[jim holtman]

If you are not going to be using factors, then you can keep everything
a character (if there are non-numerics in a column) by adding
'as.is=TRUE' as a parameter on the 'rad.table' functions.

On Mon, Aug 1, 2011 at 7:55 AM, Petr PIKAL <petr.pikal at precheza.cz> wrote:
> Hi
>
>> Hi,
>>
>> I have a dataframe that I imported from a .txt file by:
>>
>> skogTemp <- read.delim2("Skogaryd_shoot_data.txt", header=TRUE,
> fill=TRUE)
>>
>> and the data are factors, how can avoid factors from the beginning?
> Although
>> the file contains both characters and numbers.
>
> You have got an answer but here are some comments. If you have characters
> and numbers in one column the character values are converted to NA by
> as.numeric
>
>>
>> I tried to convert some of the columns from factor to numeric and as I
>> understood it you can not use only as.numeric but as.character first. I
> got
>> this warning message:
>>
>> > skogTemp_1 <- as.numeric(as.character(skogTemp_1[,2:4]))
>> Warning message:
>> NAs introduced by coercion
>
> What is skogTemp_1? I presume skogTemp is data frame and in that case you
> can not use such construction directly.
>
>>
>> I have lots of NAs in my data. Tries to check what class I had now but
>> another warning is given me:
>> > class(skogTemp_1[,2])
>
>
> skogTemp_1 is probably a vector with only one dimension therefore you get
> this error.
> class(skogTemp_1)
>
> shall give you the desired result, however I prefer
>
> ?str
>
> Regards
> Petr
>
>> Error in skogTemp_1[, 2] : incorrect number of dimensions
>> > class(skogTemp_1[1,2])
>> Error in skogTemp_1[1, 2] : incorrect number of dimensions
>>
>> frustrating... I don't know what this mean.
>>
>> Can anyone help?
>>
>> Thank you,
>> Angelica
>>
>>
>>
>> --
>> View this message in context: http://r.789695.n4.nabble.com/converting-
>>
> factor-to-numeric-gives-NAs-introduced-by-coercion-tp3703408p3703408.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
>> ______________________________________________
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>> 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.
>



-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?