scipy/base/src/_signbit.c


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/* Adapted from cephes */

static int 
signbit(double x)
{
	union
	{
		double d;
		short s[4];
		int i[2];
	} u;
	
	u.d = x;

#if SIZEOF_INT == 4

#ifdef WORDS_BIGENDIAN /* defined in pyconfig.h */
	return u.i[0] < 0;
#else
	return u.i[1] < 0;
#endif

#else  /* SIZEOF_INT != 4 */

#ifdef WORDS_BIGENDIAN
	return u.s[0] < 0;
#else
	return u.s[3] < 0;
#endif
	
#endif  /* SIZEOF_INT */
}