cf99fb40c9
Squashed commit of the following:
libs/libxx: Fix some confusing in naming. If the directory is called libxx, then the library must be libxx.a (unless perhaps LIBCXX is selected).
libs/: Fix paths in moved library directories.
libs: Brute force move of libc, libnx, and libxx to libs. Cannot yet build it in that configuration.
84 lines
2.2 KiB
C
84 lines
2.2 KiB
C
/****************************************************************************
|
|
* libs/libc/math/lib_lol.c
|
|
*
|
|
* This file is a part of NuttX:
|
|
*
|
|
* Copyright (C) 2012, 2017 Gregory Nutt. All rights reserved.
|
|
* Ported by: Darcy Gong
|
|
*
|
|
* It derives from the Rhombus OS math library by Nick Johnson which has
|
|
* a compatibile, MIT-style license:
|
|
*
|
|
* Copyright (C) 2009, 2010 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 <nuttx/config.h>
|
|
#include <nuttx/compiler.h>
|
|
|
|
#include <math.h>
|
|
#include <float.h>
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
#ifdef CONFIG_HAVE_LONG_DOUBLE
|
|
long double logl(long double x)
|
|
{
|
|
long double y;
|
|
long double y_old;
|
|
long double ey;
|
|
long double epsilon;
|
|
|
|
y = 0.0;
|
|
y_old = 1.0;
|
|
epsilon = LDBL_EPSILON;
|
|
|
|
while (y > y_old + epsilon || y < y_old - epsilon)
|
|
{
|
|
y_old = y;
|
|
ey = expl(y);
|
|
y -= (ey - x) / ey;
|
|
|
|
if (y > 700.0)
|
|
{
|
|
y = 700.0;
|
|
}
|
|
|
|
if (y < -700.0)
|
|
{
|
|
y = -700.0;
|
|
}
|
|
}
|
|
|
|
if (y == 700.0)
|
|
{
|
|
return INFINITY;
|
|
}
|
|
|
|
if (y == -700.0)
|
|
{
|
|
return INFINITY;
|
|
}
|
|
|
|
return y;
|
|
}
|
|
#endif
|