nuttx/libs/libm/libm/lib_coshf.c
Xiang Xiao 8b4ecac6c2 libc: Move math library from libs/libc/math to libs/libm/libm
to prepare the support of other implementation e.g.:
https://github.com/JuliaMath/openlibm
https://gitlab.com/gtd-gmbh/libmcs

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
2023-02-23 10:40:07 +02:00

43 lines
1.6 KiB
C

/****************************************************************************
* libs/libm/libm/lib_coshf.c
*
* This file is a part of NuttX:
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Ported by: Darcy Gong
*
* It derives from the Rhombus OS math library by Nick Johnson which has
* a compatible, MIT-style license:
*
* Copyright (C) 2009-2011 Nick Johnson <nickbjohnson4224 at gmail.com>
*
* 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 <math.h>
/****************************************************************************
* Public Functions
****************************************************************************/
float coshf(float x)
{
x = expf(x);
return ((x + (1.0F / x)) / 2.0F);
}