8b4ecac6c2
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>
68 lines
2.1 KiB
C
68 lines
2.1 KiB
C
/****************************************************************************
|
|
* libs/libm/libm/lib_atan2f.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 atan2f(float y, float x)
|
|
{
|
|
if (x > 0)
|
|
{
|
|
return atanf(y / x);
|
|
}
|
|
else if (y >= 0 && x < 0)
|
|
{
|
|
return atanf(y / x) + M_PI_F;
|
|
}
|
|
else if (y < 0)
|
|
{
|
|
if (x == 0)
|
|
{
|
|
return -M_PI_2_F;
|
|
}
|
|
else /* Can only be x < 0 */
|
|
{
|
|
return atanf(y / x) - M_PI_F;
|
|
}
|
|
}
|
|
else if (y > 0 && x == 0)
|
|
{
|
|
return M_PI_2_F;
|
|
}
|
|
else /* if (y == 0 && x == 0) Undefined but returns normally 0 */
|
|
{
|
|
return 0;
|
|
}
|
|
}
|