[R] Strange sprintf Behavior

[Jeff Newmiller]

It is poor netiquette to reply to a thread with a different subject. Please start a new thread for a new subject.

As for your question, see FAQ 7.31. This is standard floating point numerical limitations at work.
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Sent from my phone. Please excuse my brevity.

On April 2, 2014 4:32:26 AM PDT, Michael Smith <my.r.help at gmail.com> wrote:
>All,
>
>I'm getting this:
>
>> sprintf("%.17f", 0.8)
>[1] "0.80000000000000004"
>
>Where does the `4` at the end come from? Shouldn't it be zero at the
>end? Maybe I'm missing something.
>
>> sessionInfo()
>R version 3.0.2 (2013-09-25)
>Platform: x86_64-redhat-linux-gnu (64-bit)
>
>locale:
> [1] LC_CTYPE=en_US.utf8       LC_NUMERIC=C
>LC_TIME=en_US.utf8
> [4] LC_COLLATE=en_US.utf8     LC_MONETARY=en_US.utf8
>LC_MESSAGES=en_US.utf8
> [7] LC_PAPER=en_US.utf8       LC_NAME=C                 LC_ADDRESS=C
>
>[10] LC_TELEPHONE=C            LC_MEASUREMENT=en_US.utf8
>LC_IDENTIFICATION=C
>
>attached base packages:
>[1] stats     graphics  grDevices utils     datasets  methods   base
>
>
>Thanks,
>
>M
>
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