[R] Convert a character to numeric

[Duncan Murdoch]

On 09/04/2019 7:30 a.m., Jim Lemon wrote:
> Hi Bienvenue,
> Perhaps you should ask whether you really want to "sort it out". The
> warning is telling you that you are converting the NA values to NA in
> the returned numeric vector.

I don't think that's what it is saying.  I think it is saying that a 
non-NA value is being converted to NA, because R can't figure out what 
number it is.  For example,

 > as.numeric(c("1", NA))
[1]  1 NA
 > as.numeric(c("1", NA, "one"))
[1]  1 NA NA
Warning message:
NAs introduced by coercion


  I can't think of anything more sensible
> to do with NA values. You may also have character strings that cannot
> be converted into numbers, which will also generate NA values.

I think that's the only way that message will appear.

Duncan Murdoch

  Maybe a
> little example will help us to understand:
> 
> charstr<-c("5","foot","2",NA,"eyes","of","blue")
> as.numeric(charstr)
> [1]  5 NA  2 NA NA NA NA
> 
> Jim
> 
> On Tue, Apr 9, 2019 at 9:16 PM bienvenidozoma using gmail.com
> <bienvenidozoma using gmail.com> wrote:
>>
>> Hi,
>>
>> I am applyin function as.numeric to a vector having many values as NA
>> and it is giving :
>> Warning message:
>> NAs introduced by coercion
>>
>> Can anyone help me to know how to remove this warning and sor it out?
>>
>> Thanks
>> Bienvenue
>>          [[alternative HTML version deleted]]
>>
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> 
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
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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.
>