From 2e745de2f7768f4932e365f0a49edbe15a448818 Mon Sep 17 00:00:00 2001 From: patacongo Date: Sun, 28 Oct 2012 18:42:09 +0000 Subject: lib/math files not follow coding standard; float, double, and long double versions in separate files to reduce size of dumb link git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5270 42af7a65-404d-4744-a932-0658087f49c3 --- nuttx/lib/math/lib_sinl.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 nuttx/lib/math/lib_sinl.c (limited to 'nuttx/lib/math/lib_sinl.c') diff --git a/nuttx/lib/math/lib_sinl.c b/nuttx/lib/math/lib_sinl.c new file mode 100644 index 000000000..f8d9e00ed --- /dev/null +++ b/nuttx/lib/math/lib_sinl.c @@ -0,0 +1,114 @@ +/************************************************************************ + * lib/math/lib_sinl.c + * + * This file is a part of NuttX: + * + * Copyright (C) 2012 Gregory Nutt. All rights reserved. + * Ported by: Darcy Gong + * + * It derives from the Rhombs OS math library by Nick Johnson which has + * a compatibile, MIT-style license: + * + * Copyright (C) 2009-2011 Nick Johnson + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + ************************************************************************/ + +/************************************************************************ + * Included Files + ************************************************************************/ + +#include +#include + +#include +#include + +#if CONFIG_HAVE_LONG_DOUBLE + +/************************************************************************ + * Private Data + ************************************************************************/ + +static long double _ldbl_inv_fact[] = +{ + 1.0 / 1.0, // 1 / 1! + 1.0 / 6.0, // 1 / 3! + 1.0 / 120.0, // 1 / 5! + 1.0 / 5040.0, // 1 / 7! + 1.0 / 362880.0, // 1 / 9! + 1.0 / 39916800.0, // 1 / 11! + 1.0 / 6227020800.0, // 1 / 13! + 1.0 / 1307674368000.0, // 1 / 15! + 1.0 / 355687428096000.0, // 1 / 17! + 1.0 / 121645100408832000.0, // 1 / 19! +}; + +/************************************************************************ + * Public Functions + ************************************************************************/ + +long double sinl(long double x) +{ + long double x_squared; + long double sin_x; + size_t i; + + /* Move x to [-pi, pi) */ + + x = fmodl(x, 2 * M_PI); + if (x >= M_PI) + { + x -= 2 * M_PI; + } + + if (x < -M_PI) + { + x += 2 * M_PI; + } + + /* Move x to [-pi/2, pi/2) */ + + if (x >= M_PI_2) + { + x = M_PI - x; + } + + if (x < -M_PI_2) + { + x = -M_PI - x; + } + + x_squared = x * x; + sin_x = 0.0; + + /* Perform Taylor series approximation for sin(x) with ten terms */ + + for (i = 0; i < 10; i++) + { + if (i % 2 == 0) + { + sin_x += x * _ldbl_inv_fact[i]; + } + else + { + sin_x -= x * _ldbl_inv_fact[i]; + } + + x *= x_squared; + } + + return sin_x; +} +#endif -- cgit v1.2.3