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35 static char sccsid[] = "@(#)fmod.c 8.1 (Berkeley) 6/4/93";
43 * double fmod(double x, double y)
47 * The fmod function computes the floating-point remainder of x/y.
51 * The fmod function returns the value x-i*y, for some integer i
52 * such that, if y is nonzero, the result has the same sign as x and
53 * magnitude less than the magnitude of y.
57 * fmod(x,0) traps/faults on floating-point divided-by-zero.
59 * On IEEE-754 conforming machines with "isnan()" primitive,
61 * fmod(x,0), fmod(INF,y) are invalid operations and NaN is returned.
64 #if !defined(vax) && !defined(tahoe)
65 extern int isnan(),finite();
66 #endif /* !defined(vax) && !defined(tahoe) */
67 extern double frexp(),ldexp(),fabs();
75 #endif /* TEST_FMOD */
82 #if !defined(vax) && !defined(tahoe) /* per "fmod" manual entry, SunOS 4.0 */
83 || isnan(y) || !finite(x)
84 #endif /* !defined(vax) && !defined(tahoe) */
94 r -= w <= r ? w : w*(double)0.5;
96 return x >= (double)0 ? r : -r;
100 extern long random();
101 extern double fmod();
106 static int nfail = 0;
112 double ro = fmod(x,y),rn = _fmod(x,y);
114 (void)printf(" x = 0x%08.8x %08.8x (%24.16e)\n",x,x);
115 (void)printf(" y = 0x%08.8x %08.8x (%24.16e)\n",y,y);
116 (void)printf(" fmod = 0x%08.8x %08.8x (%24.16e)\n",ro,ro);
117 (void)printf("_fmod = 0x%08.8x %08.8x (%24.16e)\n",rn,rn);
124 register int i,cases;
128 for (i = 0; i < NTEST; i++) {
129 x = (double)random();
130 y = (double)random();
131 for (cases = 0; cases < NCASES; cases++) {
136 y = (double)1/y; break;
138 x = (double)1/x; break;
149 (void)printf("Number of failures: %d (out of a total of %d)\n",
150 nfail,NTEST*NCASES*4);
152 (void)printf("No discrepancies were found\n");
155 #endif /* TEST_FMOD */