nuttx/libs/libc/math/lib_asinl.c
Neale Ferguson 213b954a90 * Squash round() commits
- Add check in roundx() functions for infinite or NaN cases
  - Add block to avoid style warnings
  - Define long double constants and macros for infinity and nan
  - Correct return syntax to match NuttX style
  - Make c89 compliant
  - Fix definitions of INFINITY_L/NAN_L

* include/nuttx/lib/math.h - match standard naming conventions
  - Rename isinf_l to isinfl
  - Rename isinf_f to isinff
  - Add finite()
  - Add finitel()
  - Add finitef()
  - Define isnanl and isnanf
  - Define isfinite() so that it uses the appropriate macro

* libs/libc/math/lib_asinf.c
  libs/libc/math/lib_asinl.c
  libs/libc/math/lib_roundf.c
  libs/libc/math/lib_roundl.c
  libs/libc/math/lib_sqrtf.c
  libs/libc/math/lib_sqrtl.c
  - Use renamed macros
  - Use correct NAN_x or INFINIT_x macro on returns
2022-09-08 20:57:27 +08:00

94 lines
2.6 KiB
C

/****************************************************************************
* libs/libc/math/lib_asinl.c
*
* This file is a part of NuttX:
*
* Copyright (C) 2012, 2016 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 <nuttx/config.h>
#include <nuttx/compiler.h>
#include <math.h>
#include <float.h>
#ifdef CONFIG_HAVE_LONG_DOUBLE
/****************************************************************************
* Public Functions
****************************************************************************/
static long double asinl_aux(long double x)
{
long double y;
long double y_cos;
long double y_sin;
y = 0.0;
y_sin = 0.0;
while (fabsl(y_sin - x) > DBL_EPSILON)
{
y_cos = cosl(y);
y -= (y_sin - x) / y_cos;
y_sin = sinl(y);
}
return y;
}
/****************************************************************************
* Public Functions
****************************************************************************/
long double asinl(long double x)
{
long double y;
/* Verify that the input value is in the domain of the function */
if (x < -1.0 || x > 1.0 || isnanl(x))
{
return NAN_L;
}
/* if x is > sqrt(2), use identity for faster convergence */
if (fabsl(x) > 0.71)
{
y = M_PI_2 - asinl_aux(sqrtl(1.0 - x * x));
y = copysignl(y, x);
}
else
{
y = asinl_aux(x);
}
return y;
}
#endif /* CONFIG_HAVE_LONG_DOUBLE */