diff options
Diffstat (limited to 'tests')
| -rw-r--r-- | tests/tj1.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/tests/tj1.c b/tests/tj1.c index 534b4486c..a9bc4b08a 100644 --- a/tests/tj1.c +++ b/tests/tj1.c @@ -27,6 +27,45 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., #define REDUCE_EMAX 262143 /* otherwise arg. reduction is too expensive */ #include "tgeneric.c" +/* test for small input, where j1(x) = x/2 - x^3/16 + ... */ +static void +test_small (void) +{ + mpfr_t x, y; + int inex, sign; + mpfr_exp_t e, emin; + + mpfr_init2 (x, 10); + mpfr_init2 (y, 10); + emin = mpfr_get_emin (); + for (e = -4; e >= -30; e--) + { + if (e == -30) + { + e = mpfr_get_emin_min () - 1; + mpfr_set_emin (e + 1); + } + for (sign = -1; sign <= 1; sign += 2) + { + mpfr_set_si_2exp (x, sign, e, MPFR_RNDN); + inex = mpfr_j1 (y, x, MPFR_RNDN); + if (e >= -29) + { + MPFR_ASSERTN(mpfr_cmp_si_2exp (y, sign, e - 1) == 0); + MPFR_ASSERTN(inex * sign > 0); + } + else + { + MPFR_ASSERTN(mpfr_zero_p (y)); + MPFR_ASSERTN(mpfr_signbit(y) ^ (sign > 0)); + } + } + } + mpfr_set_emin (emin); + mpfr_clear (x); + mpfr_clear (y); +} + int main (int argc, char *argv[]) { @@ -34,6 +73,8 @@ main (int argc, char *argv[]) tests_start_mpfr (); + test_small (); + mpfr_init (x); mpfr_init (y); |