RCP<const Integer> lucas(unsigned long n)
{
mpz_class f;
mpz_lucnum_ui(f.get_mpz_t(), n);
return integer(f);
}
void
check_sequence (int argc, char *argv[])
{
unsigned long n;
unsigned long limit = 100 * BITS_PER_MP_LIMB;
mpz_t want_ln, want_ln1, got_ln, got_ln1;
if (argc > 1 && argv[1][0] == 'x')
limit = ULONG_MAX;
else if (argc > 1)
limit = atoi (argv[1]);
/* start at n==0 */
mpz_init_set_si (want_ln1, -1); /* L[-1] */
mpz_init_set_ui (want_ln, 2); /* L[0] */
mpz_init (got_ln);
mpz_init (got_ln1);
for (n = 0; n < limit; n++)
{
mpz_lucnum2_ui (got_ln, got_ln1, n);
MPZ_CHECK_FORMAT (got_ln);
MPZ_CHECK_FORMAT (got_ln1);
if (mpz_cmp (got_ln, want_ln) != 0 || mpz_cmp (got_ln1, want_ln1) != 0)
{
printf ("mpz_lucnum2_ui(%lu) wrong\n", n);
mpz_trace ("want ln ", want_ln);
mpz_trace ("got ln ", got_ln);
mpz_trace ("want ln1", want_ln1);
mpz_trace ("got ln1", got_ln1);
abort ();
}
mpz_lucnum_ui (got_ln, n);
MPZ_CHECK_FORMAT (got_ln);
if (mpz_cmp (got_ln, want_ln) != 0)
{
printf ("mpz_lucnum_ui(%lu) wrong\n", n);
mpz_trace ("want ln", want_ln);
mpz_trace ("got ln", got_ln);
abort ();
}
mpz_add (want_ln1, want_ln1, want_ln); /* L[n+1] = L[n] + L[n-1] */
mpz_swap (want_ln1, want_ln);
}
mpz_clear (want_ln);
mpz_clear (want_ln1);
mpz_clear (got_ln);
mpz_clear (got_ln1);
}
static PyObject *
GMPy_MPZ_Function_Lucas(PyObject *self, PyObject *other)
{
MPZ_Object *result = NULL;
unsigned long n;
n = c_ulong_From_Integer(other);
if (n == (unsigned long)(-1) && PyErr_Occurred()) {
return NULL;
}
if ((result = GMPy_MPZ_New(NULL))) {
mpz_lucnum_ui(result->z, n);
}
return (PyObject*)result;
}
