[R] Problem with <= (less than or equal): not giving the expected result

[PIKAL Petr]

Hi

> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of S Ellison
> Sent: Wednesday, April 6, 2016 12:35 PM
> To: Rainer Johannes <Johannes.Rainer at eurac.edu>; r-help at r-project.org
> Subject: Re: [R] Problem with <= (less than or equal): not giving the expected
> result
>
> > Apparently, abs(1 - 0.95) is not equal to 0.05, which I find however
> > quite disturbing.
>
> It's normal.* See R FAQ 7.31 in the html help system.
>
> S Ellison
>
> *... and common to all computers that use binary.

The main issue is that when using Excel you do not experience normally such issues, probably because Excel silently decide how to express precision of decimal values.

=+ABS(1-0.995) is equal to 0.005, however
=+ABS(1-0.9995) is not equal to 0.0005

So it when Excel (Excel 2016) users do not use numbers smaller than 0.005 they do not find this behaviour.

Cheers
Petr



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