From d032e0d29b6ed9d3844916ada0ead19c3190ff9a Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Tue, 25 Sep 2012 19:43:49 +0000 Subject: Fix inaccuracy of clog, clog10 near |z| = 1 (bug 13629). --- math/s_clog10f.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'math/s_clog10f.c') diff --git a/math/s_clog10f.c b/math/s_clog10f.c index c61e8af8ce..1789f1aedb 100644 --- a/math/s_clog10f.c +++ b/math/s_clog10f.c @@ -90,6 +90,19 @@ __clog10f (__complex__ float x) d2m1 += absy * absy; __real__ result = __log1pf (d2m1) * ((float) M_LOG10E / 2.0f); } + else if (absx < 1.0f + && absx >= 0.75f + && absy < FLT_EPSILON / 2.0f + && scale == 0) + { + float d2m1 = (absx - 1.0f) * (absx + 1.0f); + __real__ result = __log1pf (d2m1) * ((float) M_LOG10E / 2.0f); + } + else if (absx < 1.0f && (absx >= 0.75f || absy >= 0.5f) && scale == 0) + { + float d2m1 = __x2y2m1f (absx, absy); + __real__ result = __log1pf (d2m1) * ((float) M_LOG10E / 2.0f); + } else { float d = __ieee754_hypotf (absx, absy); -- cgit 1.4.1