[R] as.numeric looses precision

[PIKAL Petr]

Hi

As already mentioned it is a matter of printing result on your console.

> p <- "1087.003489"
> as.numeric(p, digits=6)
[1] 1087.003
> options(digits=20)
> as.numeric(p)
[1] 1087.0034889999999

The other problem is that when using PC you run into FAQ 7.31 decimal issue.

"1087.003489" number can not be represented precisely in binary arithmetic.

Cheers
Petr


> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Bos,
> Roger
> Sent: Thursday, July 02, 2015 3:55 PM
> To: r-help at r-project.org
> Subject: [R] as.numeric looses precision
>
> I have a string that contains a number and when I convert it to a
> number I loose precision and I would like to know if there is a way to
> avoid that.  Here is my example:
>
> p <- "1087.003489"
> as.numeric(p, digits=6)
>
> R gives me 1087.003:
>
> > p <- "1087.003489"
> > as.numeric(p, digits=6)
> [1] 1087.003
>
> I would be nice if I could keep all the decimal places after the
> conversion.
>
> Thanks,
>
> Roger
>
>
>
>
>
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