[R] R-1.7.1 regression test failure on alphaev68-dec-osf5.1

Jeff Lewis jlewis at genomecorp.com
Wed Jun 25 17:15:32 CEST 2003


> > Thanks for the quick response.  The two sides of the equality are
> > definately different.  Here's what I'm seeing
> > 
> > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> > > pi
> > [1] 3.141593
> > 
> > > 1i
> > [1] 0+1i
> > 
> > > pi*1i
> > [1] 0+3.141593i
> > 
> > > exp(pi*1i)
> > [1] -1+1.224647e-16i
> > 
> > > log(exp(pi*1i))
> > [1] 0+3.141593i
> > 
> > > log(exp(pi*1i)) / 1i
> > 
> > [1] 3.141593+0i
> > 
> > > pi - log(exp(pi*1i)) / 1i
> > [1] 4.440892e-16+0i
> > 
> > > Mod(pi - log(exp(pi*1i)) / 1i)
> > [1] 4.440892e-16
> > 
> > > .Machine$double.eps
> > [1] 2.220446e-16
> > 
> > > Mod(pi - log(exp(pi*1i)) / 1i) < .Machine$double.eps
> > [1] FALSE
> > 
> > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> > 
> > I get the same thing from R 1.6.2, which I compiled about six months
> > ago.  Is there anything I can/should do to fix this?
> 
> Not really. It seems that your platform just has slightly less
> accurate complex log/exp routines than the most common ones (Linux and
> Sparc/Solaris both give exact zero). Probably the check is simply
> overly stringent.
> 
> You might want to change the check to say  ... < 3*.Machine$double.eps
> or so and rerun, to check whether the rest of the checks pass.



I removed this test from the file 'reg-tests-1.R' and reran the checks.
All other checks passed with flying colors.

Thanks for the help.




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