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33 * @(#)fmod.c 8.1 (Berkeley) 6/4/93
34 * $DragonFly: src/lib/libm/common_source/Attic/fmod.c,v 1.3 2004/10/25 19:38:45 drhodus Exp $
42 * double fmod(double x, double y)
46 * The fmod function computes the floating-point remainder of x/y.
50 * The fmod function returns the value x-i*y, for some integer i
51 * such that, if y is nonzero, the result has the same sign as x and
52 * magnitude less than the magnitude of y.
56 * fmod(x,0) traps/faults on floating-point divided-by-zero.
58 * On IEEE-754 conforming machines with "isnan()" primitive,
60 * fmod(x,0), fmod(INF,y) are invalid operations and NaN is returned.
63 #if !defined(vax) && !defined(tahoe)
64 extern int isnan(),finite();
65 #endif /* !defined(vax) && !defined(tahoe) */
66 extern double frexp(),ldexp(),fabs();
74 #endif /* TEST_FMOD */
81 #if !defined(vax) && !defined(tahoe) /* per "fmod" manual entry, SunOS 4.0 */
82 || isnan(y) || !finite(x)
83 #endif /* !defined(vax) && !defined(tahoe) */
93 r -= w <= r ? w : w*(double)0.5;
95 return x >= (double)0 ? r : -r;
100 extern double fmod();
105 static int nfail = 0;
111 double ro = fmod(x,y),rn = _fmod(x,y);
113 (void)printf(" x = 0x%08.8x %08.8x (%24.16e)\n",x,x);
114 (void)printf(" y = 0x%08.8x %08.8x (%24.16e)\n",y,y);
115 (void)printf(" fmod = 0x%08.8x %08.8x (%24.16e)\n",ro,ro);
116 (void)printf("_fmod = 0x%08.8x %08.8x (%24.16e)\n",rn,rn);
127 for (i = 0; i < NTEST; i++) {
128 x = (double)random();
129 y = (double)random();
130 for (cases = 0; cases < NCASES; cases++) {
135 y = (double)1/y; break;
137 x = (double)1/x; break;
148 (void)printf("Number of failures: %d (out of a total of %d)\n",
149 nfail,NTEST*NCASES*4);
151 (void)printf("No discrepancies were found\n");
154 #endif /* TEST_FMOD */