On Fri, Feb 7, 2014 at 8:07 AM, Martynas Venckus <marty...@venck.us> wrote:
> Yup. Does this diff fix it for you?
Yeah! It works.
And R-3's testsuite is also happy now.
Thanks a lot! And thanks to Daniel too...
ok dcoppa@ to commit it, obviously
Ciao,
David
> On 2/6/14, Daniel Dickman <didick...@gmail.com> wrote:
>> I think I recently ran into a similar issue but I suspect the root cause
>> might be the same. I think the floorl function is wrong for numbers slightly
>> larger than -1 to numbers slightly below 0. In this range floorl returns -0
>> instead of -1.
>>
>>> On Feb 5, 2014, at 3:57 AM, David Coppa <dco...@openbsd.org> wrote:
>>>
>>>
>>> Hi!
>>>
>>> I hit this problem while working on updating math/R from version
>>> 2.15.3 to the latest version (3.0.2).
>>>
>>> It started happening since upstream switched from double functions
>>> to C99 long double functions (expl, fabsl, ...), during the R-3
>>> development cycle.
>>>
>>> Take the following reduced test-case, adapted from what R's code
>>> does:
>>>
>>> ---8<---
>>>
>>> #include <stdio.h>
>>> #include <stdlib.h>
>>> #include <math.h>
>>>
>>> int main(void) {
>>> double theta = 1;
>>> long double lambda, pr, pr2;
>>>
>>> lambda = (0.5*theta);
>>> pr = exp(-lambda);
>>> pr2 = expl(-lambda);
>>>
>>> printf("theta == %g, pr == %Lg, pr2 == %Lg\n", theta, pr, pr2);
>>> exit(0);
>>> }
>>>
>>> ---8<---
>>>
>>> This produces the following output on Linux (x86_64):
>>>
>>> theta == 1, pr == 0.606531, pr2 == 0.606531
>>>
>>> While on OpenBSD -current amd64:
>>>
>>> theta == 1, pr == 0.606531, pr2 == nan
>>>
>>> And indeed R-3's testsuite fails with the error message
>>> "NaNs produced":
>>>
>>> Warning in pchisq(1e-300, df = 0, ncp = lam) : NaNs produced
>>>> stopifnot(all.equal(p00, exp(-lam/2)),
>>> + all.equal(p.0, exp(-lam/2)))
>>> Error: all.equal(p.0, exp(-lam/2)) is not TRUE
>>> Execution halted
>>>
>>> Is this a bug in our expl() ?
>>>
>>> Ciao,
>>> David
>>>
>>
