diff options
| -rw-r--r-- | exp.c | 3 | ||||
| -rw-r--r-- | tests/texp.c | 16 |
2 files changed, 17 insertions, 2 deletions
@@ -83,7 +83,8 @@ mpfr_exp (mpfr_ptr y, mpfr_srcptr x, mp_rnd_t rnd_mode) int signx = MPFR_SIGN(x); MPFR_SET_POS(y); - if (MPFR_IS_NEG_SIGN(signx) && (rnd_mode == GMP_RNDD)) + if (MPFR_IS_NEG_SIGN(signx) && (rnd_mode == GMP_RNDD || + rnd_mode == GMP_RNDZ)) { mpfr_setmax (y, 0); /* y = 1 - epsilon */ return -1; diff --git a/tests/texp.c b/tests/texp.c index 44f84d813..8127fb597 100644 --- a/tests/texp.c +++ b/tests/texp.c @@ -250,12 +250,16 @@ check_special () if (mpfr_cmp_ui_2exp (y, 3, -2)) { printf ("Error for exp(-1/16), prec=2, RNDD\n"); + printf ("expected 0.11, got "); + mpfr_dump (y); exit (1); } mpfr_exp (y, x, GMP_RNDZ); - if (mpfr_cmp_ui (y, 1)) + if (mpfr_cmp_ui_2exp (y, 3, -2)) { printf ("Error for exp(-1/16), prec=2, RNDZ\n"); + printf ("expected 0.11, got "); + mpfr_dump (y); exit (1); } mpfr_set_str_binary (x, "0.1E-3"); @@ -361,6 +365,16 @@ check_inexact (void) mpfr_out_str (stdout, 16, 0, x, GMP_RNDN); putchar ('\n'); } + /* bug found by Guillaume Melquiond, 13 Sep 2005 */ + mpfr_set_prec (x, 53); + mpfr_set_str_binary (x, "-1E-400"); + mpfr_exp (x, x, GMP_RNDZ); + if (mpfr_cmp_ui (x, 1) == 0) + { + printf ("Error for exp(-2^(-400))\n"); + exit (1); + } + mpfr_clear (x); mpfr_clear (y); } |