Date: Mon, 15 Jun 2015 20:40:45 +0000 (UTC) From: Tijl Coosemans <tijl@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r284427 - head/lib/msun/src Message-ID: <201506152040.t5FKejiB059636@svn.freebsd.org>
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Author: tijl Date: Mon Jun 15 20:40:44 2015 New Revision: 284427 URL: https://svnweb.freebsd.org/changeset/base/284427 Log: - Change comments to be more consistent with s_ccosh.c and s_csinh.c. - Fix a case where NaNs were not mixed correctly and signalling NaNs were not converted to quiet NaNs. - Eliminate two negations from ctan(z). In collaboration with: bde Modified: head/lib/msun/src/s_ctanh.c head/lib/msun/src/s_ctanhf.c Modified: head/lib/msun/src/s_ctanh.c ============================================================================== --- head/lib/msun/src/s_ctanh.c Mon Jun 15 20:16:53 2015 (r284426) +++ head/lib/msun/src/s_ctanh.c Mon Jun 15 20:40:44 2015 (r284427) @@ -25,7 +25,7 @@ */ /* - * Hyperbolic tangent of a complex argument z = x + i y. + * Hyperbolic tangent of a complex argument z = x + I y. * * The algorithm is from: * @@ -44,15 +44,15 @@ * * tanh(z) = sinh(z) / cosh(z) * - * sinh(x) cos(y) + i cosh(x) sin(y) + * sinh(x) cos(y) + I cosh(x) sin(y) * = --------------------------------- - * cosh(x) cos(y) + i sinh(x) sin(y) + * cosh(x) cos(y) + I sinh(x) sin(y) * - * cosh(x) sinh(x) / cos^2(y) + i tan(y) + * cosh(x) sinh(x) / cos^2(y) + I tan(y) * = ------------------------------------- * 1 + sinh^2(x) / cos^2(y) * - * beta rho s + i t + * beta rho s + I t * = ---------------- * 1 + beta s^2 * @@ -85,16 +85,16 @@ ctanh(double complex z) ix = hx & 0x7fffffff; /* - * ctanh(NaN + i 0) = NaN + i 0 + * ctanh(NaN +- I 0) = d(NaN) +- I 0 * - * ctanh(NaN + i y) = NaN + i NaN for y != 0 + * ctanh(NaN + I y) = d(NaN,y) + I d(NaN,y) for y != 0 * * The imaginary part has the sign of x*sin(2*y), but there's no * special effort to get this right. * - * ctanh(+-Inf +- i Inf) = +-1 +- 0 + * ctanh(+-Inf +- I Inf) = +-1 +- I 0 * - * ctanh(+-Inf + i y) = +-1 + 0 sin(2y) for y finite + * ctanh(+-Inf + I y) = +-1 + I 0 sin(2y) for y finite * * The imaginary part of the sign is unspecified. This special * case is only needed to avoid a spurious invalid exception when @@ -102,24 +102,25 @@ ctanh(double complex z) */ if (ix >= 0x7ff00000) { if ((ix & 0xfffff) | lx) /* x is NaN */ - return (CMPLX(x, (y == 0 ? y : x * y))); + return (CMPLX((x + 0) * (y + 0), + y == 0 ? y : (x + 0) * (y + 0))); SET_HIGH_WORD(x, hx - 0x40000000); /* x = copysign(1, x) */ return (CMPLX(x, copysign(0, isinf(y) ? y : sin(y) * cos(y)))); } /* - * ctanh(x + i NAN) = NaN + i NaN - * ctanh(x +- i Inf) = NaN + i NaN + * ctanh(x + I NaN) = d(NaN) + I d(NaN) + * ctanh(x +- I Inf) = dNaN + I dNaN */ if (!isfinite(y)) return (CMPLX(y - y, y - y)); /* - * ctanh(+-huge + i +-y) ~= +-1 +- i 2sin(2y)/exp(2x), using the + * ctanh(+-huge +- I y) ~= +-1 +- I 2sin(2y)/exp(2x), using the * approximation sinh^2(huge) ~= exp(2*huge) / 4. * We use a modified formula to avoid spurious overflow. */ - if (ix >= 0x40360000) { /* x >= 22 */ + if (ix >= 0x40360000) { /* |x| >= 22 */ double exp_mx = exp(-fabs(x)); return (CMPLX(copysign(1, x), 4 * sin(y) * cos(y) * exp_mx * exp_mx)); @@ -138,7 +139,7 @@ double complex ctan(double complex z) { - /* ctan(z) = -I * ctanh(I * z) */ - z = ctanh(CMPLX(-cimag(z), creal(z))); - return (CMPLX(cimag(z), -creal(z))); + /* ctan(z) = -I * ctanh(I * z) = I * conj(ctanh(I * conj(z))) */ + z = ctanh(CMPLX(cimag(z), creal(z))); + return (CMPLX(cimag(z), creal(z))); } Modified: head/lib/msun/src/s_ctanhf.c ============================================================================== --- head/lib/msun/src/s_ctanhf.c Mon Jun 15 20:16:53 2015 (r284426) +++ head/lib/msun/src/s_ctanhf.c Mon Jun 15 20:40:44 2015 (r284427) @@ -60,7 +60,7 @@ ctanhf(float complex z) if (!isfinite(y)) return (CMPLXF(y - y, y - y)); - if (ix >= 0x41300000) { /* x >= 11 */ + if (ix >= 0x41300000) { /* |x| >= 11 */ float exp_mx = expf(-fabsf(x)); return (CMPLXF(copysignf(1, x), 4 * sinf(y) * cosf(y) * exp_mx * exp_mx)); @@ -78,7 +78,7 @@ float complex ctanf(float complex z) { - z = ctanhf(CMPLXF(-cimagf(z), crealf(z))); - return (CMPLXF(cimagf(z), -crealf(z))); + z = ctanhf(CMPLXF(cimagf(z), crealf(z))); + return (CMPLXF(cimagf(z), crealf(z))); }
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