double gsl_sf_coupling_6j(int two_ja, int two_jb, int two_jc,
int two_jd, int two_je, int two_jf)
{
EVAL_RESULT(gsl_sf_coupling_6j_e(two_ja, two_jb, two_jc,
two_jd, two_je, two_jf,
&result));
}
int
gsl_sf_coupling_6j_INCORRECT_e(int two_ja, int two_jb, int two_jc,
int two_jd, int two_je, int two_jf,
gsl_sf_result * result)
{
return gsl_sf_coupling_6j_e(two_ja, two_jb, two_je, two_jd, two_jc, two_jf, result);
}
int
gsl_sf_coupling_RacahW_e(int two_ja, int two_jb, int two_jc,
int two_jd, int two_je, int two_jf,
gsl_sf_result * result)
{
int status = gsl_sf_coupling_6j_e(two_ja, two_jb, two_je, two_jd, two_jc, two_jf, result);
int phase_sum = (two_ja + two_jb + two_jc + two_jd)/2;
result->val *= ( GSL_IS_ODD(phase_sum) ? -1.0 : 1.0 );
return status;
}
static VALUE rb_gsl_sf_coupling_6j_e(VALUE obj, VALUE two_ja, VALUE two_jb, VALUE two_jc, VALUE two_jd, VALUE two_je, VALUE two_jf)
{
gsl_sf_result *rslt = NULL;
VALUE v;
// local variable "status" declared and set, but never used
//int status;
CHECK_FIXNUM(two_ja); CHECK_FIXNUM(two_jb); CHECK_FIXNUM(two_jc);
CHECK_FIXNUM(two_jd); CHECK_FIXNUM(two_je); CHECK_FIXNUM(two_jf);
v = Data_Make_Struct(cgsl_sf_result, gsl_sf_result, 0, free, rslt);
/*status =*/ gsl_sf_coupling_6j_e(FIX2INT(two_ja), FIX2INT(two_jb),
FIX2INT(two_jc), FIX2INT(two_jd),
FIX2INT(two_je), FIX2INT(two_jf),
rslt);
return v;
}
int
gsl_sf_coupling_9j_e(int two_ja, int two_jb, int two_jc,
int two_jd, int two_je, int two_jf,
int two_jg, int two_jh, int two_ji,
gsl_sf_result * result)
{
/* CHECK_POINTER(result) */
if( two_ja < 0 || two_jb < 0 || two_jc < 0
|| two_jd < 0 || two_je < 0 || two_jf < 0
|| two_jg < 0 || two_jh < 0 || two_ji < 0
) {
DOMAIN_ERROR(result);
}
else if( triangle_selection_fails(two_ja, two_jb, two_jc)
|| triangle_selection_fails(two_jd, two_je, two_jf)
|| triangle_selection_fails(two_jg, two_jh, two_ji)
|| triangle_selection_fails(two_ja, two_jd, two_jg)
|| triangle_selection_fails(two_jb, two_je, two_jh)
|| triangle_selection_fails(two_jc, two_jf, two_ji)
) {
result->val = 0.0;
result->err = 0.0;
return GSL_SUCCESS;
}
else {
int tk;
int tkmin = locMax3(abs(two_ja-two_ji), abs(two_jh-two_jd), abs(two_jb-two_jf));
int tkmax = locMin3(two_ja + two_ji, two_jh + two_jd, two_jb + two_jf);
double sum_pos = 0.0;
double sum_neg = 0.0;
double sumsq_err = 0.0;
double phase;
for(tk=tkmin; tk<=tkmax; tk += 2) {
gsl_sf_result s1, s2, s3;
double term;
double term_err;
int status = 0;
status += gsl_sf_coupling_6j_e(two_ja, two_ji, tk, two_jh, two_jd, two_jg, &s1);
status += gsl_sf_coupling_6j_e(two_jb, two_jf, tk, two_jd, two_jh, two_je, &s2);
status += gsl_sf_coupling_6j_e(two_ja, two_ji, tk, two_jf, two_jb, two_jc, &s3);
if(status != GSL_SUCCESS) {
OVERFLOW_ERROR(result);
}
term = s1.val * s2.val * s3.val;
term_err = s1.err * fabs(s2.val*s3.val);
term_err += s2.err * fabs(s1.val*s3.val);
term_err += s3.err * fabs(s1.val*s2.val);
if(term >= 0.0) {
sum_pos += (tk + 1) * term;
}
else {
sum_neg -= (tk + 1) * term;
}
sumsq_err += ((tk+1) * term_err) * ((tk+1) * term_err);
}
phase = GSL_IS_ODD(tkmin) ? -1.0 : 1.0;
result->val = phase * (sum_pos - sum_neg);
result->err = 2.0 * GSL_DBL_EPSILON * (sum_pos + sum_neg);
result->err += sqrt(sumsq_err / (0.5*(tkmax-tkmin)+1.0));
result->err += 2.0 * GSL_DBL_EPSILON * (tkmax-tkmin + 2.0) * fabs(result->val);
return GSL_SUCCESS;
}
}
/**
* C++ version of gsl_sf_coupling_6j_e().
* @param two_ja Coupling coefficient in half-integer units
* @param two_jb Coupling coefficient in half-integer units
* @param two_jc Coupling coefficient in half-integer units
* @param two_jd Coupling coefficient in half-integer units
* @param two_je Coupling coefficient in half-integer units
* @param two_jf Coupling coefficient in half-integer units
* @param result Coupling coefficient in half-integer units
* @return GSL_SUCCESS or GSL_EDOM or GSL_EOVERFLW
*/
inline int coupling_6j_e( int two_ja, int two_jb, int two_jc, int two_jd, int two_je, int two_jf,
result& result ){
return gsl_sf_coupling_6j_e( two_ja, two_jb, two_jc, two_jd, two_je, two_jf, &result ); }
