[R] how to judge a virable is a integer?

[Sergio Fonda]

Don't know if this trivial reply will be useful

>a=5
>is.numeric(a)
>[1] TRUE
>b="try"
>is.numeric(b)
>[1] FALSE
 Il 18/ott/2014 16:29 "PO SU" <rhelpmaillist at 163.com> ha scritto:

>
> It's due to that, 1 is a numeric, 1.2 is a numeric, though it's true. but
> deeply, when i want to know 1 is an integer,  there seems no easy way to
> get the answer.
> So, is there anyone happen to know it?
>
>
>
>
> --
>
> PO SU
> mail: desolator88 at 163.com
> Majored in Statistics from SJTU
>
>
>
> At 2014-10-18 20:10:09, "S Ellison" <S.Ellison at LGCGroup.com> wrote:
> >> But i use a<-10/b ,  b is some value ,may be  5, maybe 5.5
> >If you do floating point arithmetic on integers you'll usually get
> floating point answers, including the 5.0.
> >
> >See FAQ 7.31 for the usual floating point problem, and ?all.equal for the
> usual answer to it. You could see if a result is close to an integer by,for
> example, using all.equal to compare it to itself after rounding.
> >
> >S
> >
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