incubator-nuttx/libc/math/lib_round.c

41 lines
987 B
C

/****************************************************************************
* lib/math/lib_round.c
*
* This file is a part of NuttX:
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* (C) 2012 Petteri Aimonen <jpa@nx.mail.kapsi.fi>
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/compiler.h>
#include <math.h>
/****************************************************************************
* Public Functions
****************************************************************************/
#ifdef CONFIG_HAVE_DOUBLE
double round(double x)
{
double f = modf(x, &x);
if (x <= 0.0 && f <= -0.5)
{
x -= 1.0;
}
if (x >= 0.0 && f >= 0.5)
{
x += 1.0;
}
return x;
}
#endif