[R] as.numeric looses precision

[MacQueen, Don]

Although Kehl and Petr have already answered the question, I would suggest
this as the simplest way to understand what is going on:

> p <- "1087.003489"
> print( as.numeric(p) , digits=16)
[1] 1087.003489

When R prints numbers, it follows various rules regarding how many decimal
places to display. You assumed it would print all six decimal places, but
that was not the case. The were there in the number itself, but not
printed.


-- 
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062





On 7/2/15, 6:54 AM, "R-help on behalf of Bos, Roger"
<r-help-bounces at r-project.org on behalf of roger.bos at rothschild.com> wrote:

>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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