int
gsl_sf_airy_Bi_deriv_e(const double x, gsl_mode_t mode, gsl_sf_result * result)
{
/* CHECK_POINTER(result) */
if(x < -1.0) {
gsl_sf_result a;
gsl_sf_result p;
int status_ap = airy_deriv_mod_phase(x, mode, &a, &p);
double s = sin(p.val);
result->val = a.val * s;
result->err = fabs(result->val * p.err) + fabs(s * a.err);
result->err += GSL_DBL_EPSILON * fabs(result->val);
return status_ap;
}
else if(x < 1.0) {
const double x3 = x*x*x;
const double x2 = x*x;
gsl_sf_result result_c1;
gsl_sf_result result_c2;
cheb_eval_mode_e(&bif_cs, x3, mode, &result_c1);
cheb_eval_mode_e(&big_cs, x3, mode, &result_c2);
result->val = x2 * (result_c1.val + 0.25) + result_c2.val + 0.5;
result->err = x2 * result_c1.err + result_c2.err;
result->err += GSL_DBL_EPSILON * fabs(result->val);
return GSL_SUCCESS;
}
else if(x < 2.0) {
const double z = (2.0*x*x*x - 9.0) / 7.0;
gsl_sf_result result_c1;
gsl_sf_result result_c2;
cheb_eval_mode_e(&bif2_cs, z, mode, &result_c1);
cheb_eval_mode_e(&big2_cs, z, mode, &result_c2);
result->val = x*x * (result_c1.val + 0.25) + result_c2.val + 0.5;
result->err = x*x * result_c1.err + result_c2.err;
result->err += GSL_DBL_EPSILON * fabs(result->val);
return GSL_SUCCESS;
}
else if(x < GSL_ROOT3_DBL_MAX*GSL_ROOT3_DBL_MAX) {
gsl_sf_result result_bps;
const double arg = 2.0*(x*sqrt(x)/3.0);
int stat_b = gsl_sf_airy_Bi_deriv_scaled_e(x, mode, &result_bps);
int stat_e = gsl_sf_exp_mult_err_e(arg, 1.5*fabs(arg*GSL_DBL_EPSILON),
result_bps.val, result_bps.err,
result);
return GSL_ERROR_SELECT_2(stat_e, stat_b);
}
else {
OVERFLOW_ERROR(result);
}
}
static VALUE Airy_Bi_deriv_scaled_e(VALUE self, VALUE x, VALUE mode) {
int ret;
gsl_sf_result r;
ret = gsl_sf_airy_Bi_deriv_scaled_e(NUM2DBL(x), NUM2UINT(mode), &r);
return RESULT(&r);
}
double gsl_sf_airy_Bi_deriv_scaled(const double x, gsl_mode_t mode)
{
EVAL_RESULT(gsl_sf_airy_Bi_deriv_scaled_e(x, mode, &result));
}
