Hi, On Mon, Apr 14, 2014 at 2:58 PM, Charles R Harris <charlesr.har...@gmail.com> wrote: > > > > On Mon, Apr 14, 2014 at 3:38 PM, Matthew Brett <matthew.br...@gmail.com> > wrote: >> >> Hi, >> >> On Mon, Apr 14, 2014 at 2:02 PM, Julian Taylor >> <jtaylor.deb...@googlemail.com> wrote: >> > The official numpy mingw binaries do not have all these math issues. >> > Only the VC builds do. >> > As mingw is fine the functions must be somewhere in the windows API but >> > no-one has contributed a fix for the VC builds to numpy yet. >> >> I'm building with mingw-w64. >> >> It looks like this works as expected from this test: >> >> #include <math.h> >> #include <stdio.h> >> >> int main() { >> double z; >> z = expm1(-0.0); >> printf("Result %f\n", z); >> } >> >> (prints -0). >> >> as does this (modified from core/src/npymath/npy_math.c.src): >> >> #include <stdio.h> >> >> double npy_expm1(double x) >> { >> if (isinf(x) && x > 0) { >> return x; >> } >> else { >> const double u = exp(x); >> >> if (u == 1.0) { >> return x; >> } else if (u - 1.0 == -1.0) { >> return -1; >> } else { >> return (u - 1.0) * x/log(u); >> } >> } >> } >> >> int main() { >> double z; >> z = npy_expm1(-0.0); >> printf("Result %f\n", z); >> } >> >> Sorry for my ignorance, but where does the `HAVE_EXPM1` symbol come from? >> > > Remember all configuration output at the beginning of the build? One of > those tries to link 'expm1{f, , l}' and sets the value of 'HAVE_EXPM1{F,,L}' > accordingly. You can find the result in the `config.h` file in the build > directory.
Ah - thanks - that got me going - somewhere. I noticed that HAVE_EXPM1 is not defined in any of OSX, my Windows build, Debian config.h - is that expected? Cheers, Matthew _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion