diff options
Diffstat (limited to 'gsl-1.9/specfunc/legendre_con.c')
-rw-r--r-- | gsl-1.9/specfunc/legendre_con.c | 1373 |
1 files changed, 1373 insertions, 0 deletions
diff --git a/gsl-1.9/specfunc/legendre_con.c b/gsl-1.9/specfunc/legendre_con.c new file mode 100644 index 0000000..6d60550 --- /dev/null +++ b/gsl-1.9/specfunc/legendre_con.c @@ -0,0 +1,1373 @@ +/* specfunc/legendre_con.c + * + * Copyright (C) 1996, 1997, 1998, 1999, 2000 Gerard Jungman + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or (at + * your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +/* Author: G. Jungman */ + +#include <config.h> +#include <gsl/gsl_math.h> +#include <gsl/gsl_errno.h> +#include <gsl/gsl_poly.h> +#include <gsl/gsl_sf_exp.h> +#include <gsl/gsl_sf_trig.h> +#include <gsl/gsl_sf_gamma.h> +#include <gsl/gsl_sf_ellint.h> +#include <gsl/gsl_sf_pow_int.h> +#include <gsl/gsl_sf_bessel.h> +#include <gsl/gsl_sf_hyperg.h> +#include <gsl/gsl_sf_legendre.h> + +#include "error.h" +#include "legendre.h" + +#define Root_2OverPi_ 0.797884560802865355879892 +#define locEPS (1000.0*GSL_DBL_EPSILON) + + +/*-*-*-*-*-*-*-*-*-*-*-* Private Section *-*-*-*-*-*-*-*-*-*-*-*/ + + +#define RECURSE_LARGE (1.0e-5*GSL_DBL_MAX) +#define RECURSE_SMALL (1.0e+5*GSL_DBL_MIN) + + +/* Continued fraction for f_{ell+1}/f_ell + * f_ell := P^{-mu-ell}_{-1/2 + I tau}(x), x < 1.0 + * + * Uses standard CF method from Temme's book. + */ +static +int +conicalP_negmu_xlt1_CF1(const double mu, const int ell, const double tau, + const double x, gsl_sf_result * result) +{ + const double RECUR_BIG = GSL_SQRT_DBL_MAX; + const int maxiter = 5000; + int n = 1; + double xi = x/(sqrt(1.0-x)*sqrt(1.0+x)); + double Anm2 = 1.0; + double Bnm2 = 0.0; + double Anm1 = 0.0; + double Bnm1 = 1.0; + double a1 = 1.0; + double b1 = 2.0*(mu + ell + 1.0) * xi; + double An = b1*Anm1 + a1*Anm2; + double Bn = b1*Bnm1 + a1*Bnm2; + double an, bn; + double fn = An/Bn; + + while(n < maxiter) { + double old_fn; + double del; + n++; + Anm2 = Anm1; + Bnm2 = Bnm1; + Anm1 = An; + Bnm1 = Bn; + an = tau*tau + (mu - 0.5 + ell + n)*(mu - 0.5 + ell + n); + bn = 2.0*(ell + mu + n) * xi; + An = bn*Anm1 + an*Anm2; + Bn = bn*Bnm1 + an*Bnm2; + + if(fabs(An) > RECUR_BIG || fabs(Bn) > RECUR_BIG) { + An /= RECUR_BIG; + Bn /= RECUR_BIG; + Anm1 /= RECUR_BIG; + Bnm1 /= RECUR_BIG; + Anm2 /= RECUR_BIG; + Bnm2 /= RECUR_BIG; + } + + old_fn = fn; + fn = An/Bn; + del = old_fn/fn; + + if(fabs(del - 1.0) < 2.0*GSL_DBL_EPSILON) break; + } + + result->val = fn; + result->err = 4.0 * GSL_DBL_EPSILON * (sqrt(n) + 1.0) * fabs(fn); + + if(n >= maxiter) + GSL_ERROR ("error", GSL_EMAXITER); + else + return GSL_SUCCESS; +} + + +/* Continued fraction for f_{ell+1}/f_ell + * f_ell := P^{-mu-ell}_{-1/2 + I tau}(x), x >= 1.0 + * + * Uses Gautschi (Euler) equivalent series. + */ +static +int +conicalP_negmu_xgt1_CF1(const double mu, const int ell, const double tau, + const double x, gsl_sf_result * result) +{ + const int maxk = 20000; + const double gamma = 1.0-1.0/(x*x); + const double pre = sqrt(x-1.0)*sqrt(x+1.0) / (x*(2.0*(ell+mu+1.0))); + double tk = 1.0; + double sum = 1.0; + double rhok = 0.0; + int k; + + for(k=1; k<maxk; k++) { + double tlk = 2.0*(ell + mu + k); + double l1k = (ell + mu - 0.5 + 1.0 + k); + double ak = -(tau*tau + l1k*l1k)/(tlk*(tlk+2.0)) * gamma; + rhok = -ak*(1.0 + rhok)/(1.0 + ak*(1.0 + rhok)); + tk *= rhok; + sum += tk; + if(fabs(tk/sum) < GSL_DBL_EPSILON) break; + } + + result->val = pre * sum; + result->err = fabs(pre * tk); + result->err += 2.0 * GSL_DBL_EPSILON * (sqrt(k) + 1.0) * fabs(pre*sum); + + if(k >= maxk) + GSL_ERROR ("error", GSL_EMAXITER); + else + return GSL_SUCCESS; +} + + +/* Implementation of large negative mu asymptotic + * [Dunster, Proc. Roy. Soc. Edinburgh 119A, 311 (1991), p. 326] + */ + +inline +static double olver_U1(double beta2, double p) +{ + return (p-1.0)/(24.0*(1.0+beta2)) * (3.0 + beta2*(2.0 + 5.0*p*(1.0+p))); +} + +inline +static double olver_U2(double beta2, double p) +{ + double beta4 = beta2*beta2; + double p2 = p*p; + double poly1 = 4.0*beta4 + 84.0*beta2 - 63.0; + double poly2 = 16.0*beta4 + 90.0*beta2 - 81.0; + double poly3 = beta2*p2*(97.0*beta2 - 432.0 + 77.0*p*(beta2-6.0) - 385.0*beta2*p2*(1.0 + p)); + return (1.0-p)/(1152.0*(1.0+beta2)) * (poly1 + poly2 + poly3); +} + +static const double U3c1[] = { -1307.0, -1647.0, 3375.0, 3675.0 }; +static const double U3c2[] = { 29366.0, 35835.0, -252360.0, -272630.0, + 276810.0, 290499.0 }; +static const double U3c3[] = { -29748.0, -8840.0, 1725295.0, 1767025.0, + -7313470.0, -754778.0, 6309875.0, 6480045.0 }; +static const double U3c4[] = { 2696.0, -16740.0, -524250.0, -183975.0, + 14670540.0, 14172939.0, -48206730.0, -48461985.0, + 36756720.0, 37182145.0 }; +static const double U3c5[] = { 9136.0, 22480.0, 12760.0, + -252480.0, -4662165.0, -1705341.0, + 92370135.0, 86244015.0, -263678415.0, + -260275015.0, 185910725.0, 185910725.0 }; + +#if 0 +static double olver_U3(double beta2, double p) +{ + double beta4 = beta2*beta2; + double beta6 = beta4*beta2; + double opb2s = (1.0+beta2)*(1.0+beta2); + double den = 39813120.0 * opb2s*opb2s; + double poly1 = gsl_poly_eval(U3c1, 4, p); + double poly2 = gsl_poly_eval(U3c2, 6, p); + double poly3 = gsl_poly_eval(U3c3, 8, p); + double poly4 = gsl_poly_eval(U3c4, 10, p); + double poly5 = gsl_poly_eval(U3c5, 12, p); + + return (p-1.0)*( 1215.0*poly1 + 324.0*beta2*poly2 + + 54.0*beta4*poly3 + 12.0*beta6*poly4 + + beta4*beta4*poly5 + ) / den; +} +#endif /* 0 */ + + +/* Large negative mu asymptotic + * P^{-mu}_{-1/2 + I tau}, mu -> Inf + * |x| < 1 + * + * [Dunster, Proc. Roy. Soc. Edinburgh 119A, 311 (1991), p. 326] + */ +int +gsl_sf_conicalP_xlt1_large_neg_mu_e(double mu, double tau, double x, + gsl_sf_result * result, double * ln_multiplier) +{ + double beta = tau/mu; + double beta2 = beta*beta; + double S = beta * acos((1.0-beta2)/(1.0+beta2)); + double p = x/sqrt(beta2*(1.0-x*x) + 1.0); + gsl_sf_result lg_mup1; + int lg_stat = gsl_sf_lngamma_e(mu+1.0, &lg_mup1); + double ln_pre_1 = 0.5*mu*(S - log(1.0+beta2) + log((1.0-p)/(1.0+p))) - lg_mup1.val; + double ln_pre_2 = -0.25 * log(1.0 + beta2*(1.0-x)); + double ln_pre_3 = -tau * atan(p*beta); + double ln_pre = ln_pre_1 + ln_pre_2 + ln_pre_3; + double sum = 1.0 - olver_U1(beta2, p)/mu + olver_U2(beta2, p)/(mu*mu); + + if(sum == 0.0) { + result->val = 0.0; + result->err = 0.0; + *ln_multiplier = 0.0; + return GSL_SUCCESS; + } + else { + int stat_e = gsl_sf_exp_mult_e(ln_pre, sum, result); + if(stat_e != GSL_SUCCESS) { + result->val = sum; + result->err = 2.0 * GSL_DBL_EPSILON * fabs(sum); + *ln_multiplier = ln_pre; + } + else { + *ln_multiplier = 0.0; + } + return lg_stat; + } +} + + +/* Implementation of large tau asymptotic + * + * A_n^{-mu}, B_n^{-mu} [Olver, p.465, 469] + */ + +inline +static double olver_B0_xi(double mu, double xi) +{ + return (1.0 - 4.0*mu*mu)/(8.0*xi) * (1.0/tanh(xi) - 1.0/xi); +} + +static double olver_A1_xi(double mu, double xi, double x) +{ + double B = olver_B0_xi(mu, xi); + double psi; + if(fabs(x - 1.0) < GSL_ROOT4_DBL_EPSILON) { + double y = x - 1.0; + double s = -1.0/3.0 + y*(2.0/15.0 - y *(61.0/945.0 - 452.0/14175.0*y)); + psi = (4.0*mu*mu - 1.0)/16.0 * s; + } + else { + psi = (4.0*mu*mu - 1.0)/16.0 * (1.0/(x*x-1.0) - 1.0/(xi*xi)); + } + return 0.5*xi*xi*B*B + (mu+0.5)*B - psi + mu/6.0*(0.25 - mu*mu); +} + +inline +static double olver_B0_th(double mu, double theta) +{ + return -(1.0 - 4.0*mu*mu)/(8.0*theta) * (1.0/tan(theta) - 1.0/theta); +} + +static double olver_A1_th(double mu, double theta, double x) +{ + double B = olver_B0_th(mu, theta); + double psi; + if(fabs(x - 1.0) < GSL_ROOT4_DBL_EPSILON) { + double y = 1.0 - x; + double s = -1.0/3.0 + y*(2.0/15.0 - y *(61.0/945.0 - 452.0/14175.0*y)); + psi = (4.0*mu*mu - 1.0)/16.0 * s; + } + else { + psi = (4.0*mu*mu - 1.0)/16.0 * (1.0/(x*x-1.0) + 1.0/(theta*theta)); + } + return -0.5*theta*theta*B*B + (mu+0.5)*B - psi + mu/6.0*(0.25 - mu*mu); +} + + +/* Large tau uniform asymptotics + * P^{-mu}_{-1/2 + I tau} + * 1 < x + * tau -> Inf + * [Olver, p. 469] + */ +int +gsl_sf_conicalP_xgt1_neg_mu_largetau_e(const double mu, const double tau, + const double x, double acosh_x, + gsl_sf_result * result, double * ln_multiplier) +{ + double xi = acosh_x; + double ln_xi_pre; + double ln_pre; + double sumA, sumB, sum; + double arg; + gsl_sf_result J_mup1; + gsl_sf_result J_mu; + double J_mum1; + + if(xi < GSL_ROOT4_DBL_EPSILON) { + ln_xi_pre = -xi*xi/6.0; /* log(1.0 - xi*xi/6.0) */ + } + else { + gsl_sf_result lnshxi; + gsl_sf_lnsinh_e(xi, &lnshxi); + ln_xi_pre = log(xi) - lnshxi.val; /* log(xi/sinh(xi) */ + } + + ln_pre = 0.5*ln_xi_pre - mu*log(tau); + + arg = tau*xi; + + gsl_sf_bessel_Jnu_e(mu + 1.0, arg, &J_mup1); + gsl_sf_bessel_Jnu_e(mu, arg, &J_mu); + J_mum1 = -J_mup1.val + 2.0*mu/arg*J_mu.val; /* careful of mu < 1 */ + + sumA = 1.0 - olver_A1_xi(-mu, xi, x)/(tau*tau); + sumB = olver_B0_xi(-mu, xi); + sum = J_mu.val * sumA - xi/tau * J_mum1 * sumB; + + if(sum == 0.0) { + result->val = 0.0; + result->err = 0.0; + *ln_multiplier = 0.0; + return GSL_SUCCESS; + } + else { + int stat_e = gsl_sf_exp_mult_e(ln_pre, sum, result); + if(stat_e != GSL_SUCCESS) { + result->val = sum; + result->err = 2.0 * GSL_DBL_EPSILON * fabs(sum); + *ln_multiplier = ln_pre; + } + else { + *ln_multiplier = 0.0; + } + return GSL_SUCCESS; + } +} + + +/* Large tau uniform asymptotics + * P^{-mu}_{-1/2 + I tau} + * -1 < x < 1 + * tau -> Inf + * [Olver, p. 473] + */ +int +gsl_sf_conicalP_xlt1_neg_mu_largetau_e(const double mu, const double tau, + const double x, const double acos_x, + gsl_sf_result * result, double * ln_multiplier) +{ + double theta = acos_x; + double ln_th_pre; + double ln_pre; + double sumA, sumB, sum, sumerr; + double arg; + gsl_sf_result I_mup1, I_mu; + double I_mum1; + + if(theta < GSL_ROOT4_DBL_EPSILON) { + ln_th_pre = theta*theta/6.0; /* log(1.0 + theta*theta/6.0) */ + } + else { + ln_th_pre = log(theta/sin(theta)); + } + + ln_pre = 0.5 * ln_th_pre - mu * log(tau); + + arg = tau*theta; + gsl_sf_bessel_Inu_e(mu + 1.0, arg, &I_mup1); + gsl_sf_bessel_Inu_e(mu, arg, &I_mu); + I_mum1 = I_mup1.val + 2.0*mu/arg * I_mu.val; /* careful of mu < 1 */ + + sumA = 1.0 - olver_A1_th(-mu, theta, x)/(tau*tau); + sumB = olver_B0_th(-mu, theta); + sum = I_mu.val * sumA - theta/tau * I_mum1 * sumB; + sumerr = fabs(I_mu.err * sumA); + sumerr += fabs(I_mup1.err * theta/tau * sumB); + sumerr += fabs(I_mu.err * theta/tau * sumB * 2.0 * mu/arg); + + if(sum == 0.0) { + result->val = 0.0; + result->err = 0.0; + *ln_multiplier = 0.0; + return GSL_SUCCESS; + } + else { + int stat_e = gsl_sf_exp_mult_e(ln_pre, sum, result); + if(stat_e != GSL_SUCCESS) { + result->val = sum; + result->err = sumerr; + result->err += GSL_DBL_EPSILON * fabs(sum); + *ln_multiplier = ln_pre; + } + else { + *ln_multiplier = 0.0; + } + return GSL_SUCCESS; + } +} + + +/* Hypergeometric function which appears in the + * large x expansion below: + * + * 2F1(1/4 - mu/2 - I tau/2, 3/4 - mu/2 - I tau/2, 1 - I tau, y) + * + * Note that for the usage below y = 1/x^2; + */ +static +int +conicalP_hyperg_large_x(const double mu, const double tau, const double y, + double * reF, double * imF) +{ + const int kmax = 1000; + const double re_a = 0.25 - 0.5*mu; + const double re_b = 0.75 - 0.5*mu; + const double re_c = 1.0; + const double im_a = -0.5*tau; + const double im_b = -0.5*tau; + const double im_c = -tau; + + double re_sum = 1.0; + double im_sum = 0.0; + double re_term = 1.0; + double im_term = 0.0; + int k; + + for(k=1; k<=kmax; k++) { + double re_ak = re_a + k - 1.0; + double re_bk = re_b + k - 1.0; + double re_ck = re_c + k - 1.0; + double im_ak = im_a; + double im_bk = im_b; + double im_ck = im_c; + double den = re_ck*re_ck + im_ck*im_ck; + double re_multiplier = ((re_ak*re_bk - im_ak*im_bk)*re_ck + im_ck*(im_ak*re_bk + re_ak*im_bk)) / den; + double im_multiplier = ((im_ak*re_bk + re_ak*im_bk)*re_ck - im_ck*(re_ak*re_bk - im_ak*im_bk)) / den; + double re_tmp = re_multiplier*re_term - im_multiplier*im_term; + double im_tmp = im_multiplier*re_term + re_multiplier*im_term; + double asum = fabs(re_sum) + fabs(im_sum); + re_term = y/k * re_tmp; + im_term = y/k * im_tmp; + if(fabs(re_term/asum) < GSL_DBL_EPSILON && fabs(im_term/asum) < GSL_DBL_EPSILON) break; + re_sum += re_term; + im_sum += im_term; + } + + *reF = re_sum; + *imF = im_sum; + + if(k == kmax) + GSL_ERROR ("error", GSL_EMAXITER); + else + return GSL_SUCCESS; +} + + +/* P^{mu}_{-1/2 + I tau} + * x->Inf + */ +int +gsl_sf_conicalP_large_x_e(const double mu, const double tau, const double x, + gsl_sf_result * result, double * ln_multiplier) +{ + /* 2F1 term + */ + double y = ( x < 0.5*GSL_SQRT_DBL_MAX ? 1.0/(x*x) : 0.0 ); + double reF, imF; + int stat_F = conicalP_hyperg_large_x(mu, tau, y, &reF, &imF); + + /* f = Gamma(+i tau)/Gamma(1/2 - mu + i tau) + * FIXME: shift so it's better for tau-> 0 + */ + gsl_sf_result lgr_num, lgth_num; + gsl_sf_result lgr_den, lgth_den; + int stat_gn = gsl_sf_lngamma_complex_e(0.0,tau,&lgr_num,&lgth_num); + int stat_gd = gsl_sf_lngamma_complex_e(0.5-mu,tau,&lgr_den,&lgth_den); + + double angle = lgth_num.val - lgth_den.val + atan2(imF,reF); + + double lnx = log(x); + double lnxp1 = log(x+1.0); + double lnxm1 = log(x-1.0); + double lnpre_const = 0.5*M_LN2 - 0.5*M_LNPI; + double lnpre_comm = (mu-0.5)*lnx - 0.5*mu*(lnxp1 + lnxm1); + double lnpre_err = GSL_DBL_EPSILON * (0.5*M_LN2 + 0.5*M_LNPI) + + GSL_DBL_EPSILON * fabs((mu-0.5)*lnx) + + GSL_DBL_EPSILON * fabs(0.5*mu)*(fabs(lnxp1)+fabs(lnxm1)); + + /* result = pre*|F|*|f| * cos(angle - tau * (log(x)+M_LN2)) + */ + gsl_sf_result cos_result; + int stat_cos = gsl_sf_cos_e(angle + tau*(log(x) + M_LN2), &cos_result); + int status = GSL_ERROR_SELECT_4(stat_cos, stat_gd, stat_gn, stat_F); + if(cos_result.val == 0.0) { + result->val = 0.0; + result->err = 0.0; + return status; + } + else { + double lnFf_val = 0.5*log(reF*reF+imF*imF) + lgr_num.val - lgr_den.val; + double lnFf_err = lgr_num.err + lgr_den.err + GSL_DBL_EPSILON * fabs(lnFf_val); + double lnnoc_val = lnpre_const + lnpre_comm + lnFf_val; + double lnnoc_err = lnpre_err + lnFf_err + GSL_DBL_EPSILON * fabs(lnnoc_val); + int stat_e = gsl_sf_exp_mult_err_e(lnnoc_val, lnnoc_err, + cos_result.val, cos_result.err, + result); + if(stat_e == GSL_SUCCESS) { + *ln_multiplier = 0.0; + } + else { + result->val = cos_result.val; + result->err = cos_result.err; + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + *ln_multiplier = lnnoc_val; + } + return status; + } +} + + +/* P^{mu}_{-1/2 + I tau} first hypergeometric representation + * -1 < x < 1 + * This is more effective for |x| small, however it will work w/o + * reservation for any x < 0 because everything is positive + * definite in that case. + * + * [Kolbig, (3)] (note typo in args of gamma functions) + * [Bateman, (22)] (correct form) + */ +static +int +conicalP_xlt1_hyperg_A(double mu, double tau, double x, gsl_sf_result * result) +{ + double x2 = x*x; + double err_amp = 1.0 + 1.0/(GSL_DBL_EPSILON + fabs(1.0-fabs(x))); + double pre_val = M_SQRTPI / pow(0.5*sqrt(1-x2), mu); + double pre_err = err_amp * GSL_DBL_EPSILON * (fabs(mu)+1.0) * fabs(pre_val) ; + gsl_sf_result ln_g1, ln_g2, arg_g1, arg_g2; + gsl_sf_result F1, F2; + gsl_sf_result pre1, pre2; + double t1_val, t1_err; + double t2_val, t2_err; + + int stat_F1 = gsl_sf_hyperg_2F1_conj_e(0.25 - 0.5*mu, 0.5*tau, 0.5, x2, &F1); + int stat_F2 = gsl_sf_hyperg_2F1_conj_e(0.75 - 0.5*mu, 0.5*tau, 1.5, x2, &F2); + int status = GSL_ERROR_SELECT_2(stat_F1, stat_F2); + + gsl_sf_lngamma_complex_e(0.75 - 0.5*mu, -0.5*tau, &ln_g1, &arg_g1); + gsl_sf_lngamma_complex_e(0.25 - 0.5*mu, -0.5*tau, &ln_g2, &arg_g2); + + gsl_sf_exp_err_e(-2.0*ln_g1.val, 2.0*ln_g1.err, &pre1); + gsl_sf_exp_err_e(-2.0*ln_g2.val, 2.0*ln_g2.err, &pre2); + pre2.val *= -2.0*x; + pre2.err *= 2.0*fabs(x); + pre2.err += GSL_DBL_EPSILON * fabs(pre2.val); + + t1_val = pre1.val * F1.val; + t1_err = fabs(pre1.val) * F1.err + pre1.err * fabs(F1.val); + t2_val = pre2.val * F2.val; + t2_err = fabs(pre2.val) * F2.err + pre2.err * fabs(F2.val); + + result->val = pre_val * (t1_val + t2_val); + result->err = pre_val * (t1_err + t2_err); + result->err += pre_err * fabs(t1_val + t2_val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + + return status; +} + + +/* P^{mu}_{-1/2 + I tau} + * defining hypergeometric representation + * [Abramowitz+Stegun, 8.1.2] + * 1 < x < 3 + * effective for x near 1 + * + */ +#if 0 +static +int +conicalP_def_hyperg(double mu, double tau, double x, double * result) +{ + double F; + int stat_F = gsl_sf_hyperg_2F1_conj_renorm_e(0.5, tau, 1.0-mu, 0.5*(1.0-x), &F); + *result = pow((x+1.0)/(x-1.0), 0.5*mu) * F; + return stat_F; +} +#endif /* 0 */ + + +/* P^{mu}_{-1/2 + I tau} second hypergeometric representation + * [Zhurina+Karmazina, (3.1)] + * -1 < x < 3 + * effective for x near 1 + * + */ +#if 0 +static +int +conicalP_xnear1_hyperg_C(double mu, double tau, double x, double * result) +{ + double ln_pre, arg_pre; + double ln_g1, arg_g1; + double ln_g2, arg_g2; + double F; + + int stat_F = gsl_sf_hyperg_2F1_conj_renorm_e(0.5+mu, tau, 1.0+mu, 0.5*(1.0-x), &F); + + gsl_sf_lngamma_complex_e(0.5+mu, tau, &ln_g1, &arg_g1); + gsl_sf_lngamma_complex_e(0.5-mu, tau, &ln_g2, &arg_g2); + + ln_pre = mu*M_LN2 - 0.5*mu*log(fabs(x*x-1.0)) + ln_g1 - ln_g2; + arg_pre = arg_g1 - arg_g2; + + *result = exp(ln_pre) * F; + return stat_F; +} +#endif /* 0 */ + + +/* V0, V1 from Kolbig, m = 0 + */ +static +int +conicalP_0_V(const double t, const double f, const double tau, const double sgn, + double * V0, double * V1) +{ + double C[8]; + double T[8]; + double H[8]; + double V[12]; + int i; + T[0] = 1.0; + H[0] = 1.0; + V[0] = 1.0; + for(i=1; i<=7; i++) { + T[i] = T[i-1] * t; + H[i] = H[i-1] * (t*f); + } + for(i=1; i<=11; i++) { + V[i] = V[i-1] * tau; + } + + C[0] = 1.0; + C[1] = (H[1]-1.0)/(8.0*T[1]); + C[2] = (9.0*H[2] + 6.0*H[1] - 15.0 - sgn*8.0*T[2])/(128.0*T[2]); + C[3] = 5.0*(15.0*H[3] + 27.0*H[2] + 21.0*H[1] - 63.0 - sgn*T[2]*(16.0*H[1]+24.0))/(1024.0*T[3]); + C[4] = 7.0*(525.0*H[4] + 1500.0*H[3] + 2430.0*H[2] + 1980.0*H[1] - 6435.0 + + 192.0*T[4] - sgn*T[2]*(720.0*H[2]+1600.0*H[1]+2160.0) + ) / (32768.0*T[4]); + C[5] = 21.0*(2835.0*H[5] + 11025.0*H[4] + 24750.0*H[3] + 38610.0*H[2] + + 32175.0*H[1] - 109395.0 + T[4]*(1984.0*H[1]+4032.0) + - sgn*T[2]*(4800.0*H[3]+15120.0*H[2]+26400.0*H[1]+34320.0) + ) / (262144.0*T[5]); + C[6] = 11.0*(218295.0*H[6] + 1071630.0*H[5] + 3009825.0*H[4] + 6142500.0*H[3] + + 9398025.0*H[2] + 7936110.0*H[1] - 27776385.0 + + T[4]*(254016.0*H[2]+749952.0*H[1]+1100736.0) + - sgn*T[2]*(441000.0*H[4] + 1814400.0*H[3] + 4127760.0*H[2] + + 6552000.0*H[1] + 8353800.0 + 31232.0*T[4] + ) + ) / (4194304.0*T[6]); + + *V0 = C[0] + (-4.0*C[3]/T[1]+C[4])/V[4] + + (-192.0*C[5]/T[3]+144.0*C[6]/T[2])/V[8] + + sgn * (-C[2]/V[2] + + (-24.0*C[4]/T[2]+12.0*C[5]/T[1]-C[6])/V[6] + + (-1920.0*C[6]/T[4])/V[10] + ); + *V1 = C[1]/V[1] + (8.0*(C[3]/T[2]-C[4]/T[1])+C[5])/V[5] + + (384.0*C[5]/T[4] - 768.0*C[6]/T[3])/V[9] + + sgn * ((2.0*C[2]/T[1]-C[3])/V[3] + + (48.0*C[4]/T[3]-72.0*C[5]/T[2] + 18.0*C[6]/T[1])/V[7] + + (3840.0*C[6]/T[5])/V[11] + ); + + return GSL_SUCCESS; +} + + +/* V0, V1 from Kolbig, m = 1 + */ +static +int +conicalP_1_V(const double t, const double f, const double tau, const double sgn, + double * V0, double * V1) +{ + double Cm1; + double C[8]; + double T[8]; + double H[8]; + double V[12]; + int i; + T[0] = 1.0; + H[0] = 1.0; + V[0] = 1.0; + for(i=1; i<=7; i++) { + T[i] = T[i-1] * t; + H[i] = H[i-1] * (t*f); + } + for(i=1; i<=11; i++) { + V[i] = V[i-1] * tau; + } + + Cm1 = -1.0; + C[0] = 3.0*(1.0-H[1])/(8.0*T[1]); + C[1] = (-15.0*H[2]+6.0*H[1]+9.0+sgn*8.0*T[2])/(128.0*T[2]); + C[2] = 3.0*(-35.0*H[3] - 15.0*H[2] + 15.0*H[1] + 35.0 + sgn*T[2]*(32.0*H[1]+8.0))/(1024.0*T[3]); + C[3] = (-4725.0*H[4] - 6300.0*H[3] - 3150.0*H[2] + 3780.0*H[1] + 10395.0 + -1216.0*T[4] + sgn*T[2]*(6000.0*H[2]+5760.0*H[1]+1680.0)) / (32768.0*T[4]); + C[4] = 7.0*(-10395.0*H[5] - 23625.0*H[4] - 28350.0*H[3] - 14850.0*H[2] + +19305.0*H[1] + 57915.0 - T[4]*(6336.0*H[1]+6080.0) + + sgn*T[2]*(16800.0*H[3] + 30000.0*H[2] + 25920.0*H[1] + 7920.0) + ) / (262144.0*T[5]); + C[5] = (-2837835.0*H[6] - 9168390.0*H[5] - 16372125.0*H[4] - 18918900*H[3] + -10135125.0*H[2] + 13783770.0*H[1] + 43648605.0 + -T[4]*(3044160.0*H[2] + 5588352.0*H[1] + 4213440.0) + +sgn*T[2]*(5556600.0*H[4] + 14817600.0*H[3] + 20790000.0*H[2] + + 17297280.0*H[1] + 5405400.0 + 323072.0*T[4] + ) + ) / (4194304.0*T[6]); + C[6] = 0.0; + + *V0 = C[0] + (-4.0*C[3]/T[1]+C[4])/V[4] + + (-192.0*C[5]/T[3]+144.0*C[6]/T[2])/V[8] + + sgn * (-C[2]/V[2] + + (-24.0*C[4]/T[2]+12.0*C[5]/T[1]-C[6])/V[6] + ); + *V1 = C[1]/V[1] + (8.0*(C[3]/T[2]-C[4]/T[1])+C[5])/V[5] + + (384.0*C[5]/T[4] - 768.0*C[6]/T[3])/V[9] + + sgn * (Cm1*V[1] + (2.0*C[2]/T[1]-C[3])/V[3] + + (48.0*C[4]/T[3]-72.0*C[5]/T[2] + 18.0*C[6]/T[1])/V[7] + ); + + return GSL_SUCCESS; +} + + + +/*-*-*-*-*-*-*-*-*-*-*-* Functions with Error Codes *-*-*-*-*-*-*-*-*-*-*-*/ + +/* P^0_{-1/2 + I lambda} + */ +int +gsl_sf_conicalP_0_e(const double lambda, const double x, gsl_sf_result * result) +{ + /* CHECK_POINTER(result) */ + + if(x <= -1.0) { + DOMAIN_ERROR(result); + } + else if(x == 1.0) { + result->val = 1.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else if(lambda == 0.0) { + gsl_sf_result K; + int stat_K; + if(x < 1.0) { + const double th = acos(x); + const double s = sin(0.5*th); + stat_K = gsl_sf_ellint_Kcomp_e(s, GSL_MODE_DEFAULT, &K); + result->val = 2.0/M_PI * K.val; + result->err = 2.0/M_PI * K.err; + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_K; + } + else { + const double xi = acosh(x); + const double c = cosh(0.5*xi); + const double t = tanh(0.5*xi); + stat_K = gsl_sf_ellint_Kcomp_e(t, GSL_MODE_DEFAULT, &K); + result->val = 2.0/M_PI / c * K.val; + result->err = 2.0/M_PI / c * K.err; + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_K; + } + } + else if( (x <= 0.0 && lambda < 1000.0) + || (x < 0.1 && lambda < 17.0) + || (x < 0.2 && lambda < 5.0 ) + ) { + return conicalP_xlt1_hyperg_A(0.0, lambda, x, result); + } + else if( (x <= 0.2 && lambda < 17.0) + || (x <= 1.5 && lambda < 20.0) + ) { + return gsl_sf_hyperg_2F1_conj_e(0.5, lambda, 1.0, (1.0-x)/2, result); + } + else if(1.5 < x && lambda < GSL_MAX(x,20.0)) { + gsl_sf_result P; + double lm; + int stat_P = gsl_sf_conicalP_large_x_e(0.0, lambda, x, + &P, &lm + ); + int stat_e = gsl_sf_exp_mult_err_e(lm, 2.0*GSL_DBL_EPSILON * fabs(lm), + P.val, P.err, + result); + return GSL_ERROR_SELECT_2(stat_e, stat_P); + } + else { + double V0, V1; + if(x < 1.0) { + double th = acos(x); + double sth = sqrt(1.0-x*x); /* sin(th) */ + gsl_sf_result I0, I1; + int stat_I0 = gsl_sf_bessel_I0_scaled_e(th * lambda, &I0); + int stat_I1 = gsl_sf_bessel_I1_scaled_e(th * lambda, &I1); + int stat_I = GSL_ERROR_SELECT_2(stat_I0, stat_I1); + int stat_V = conicalP_0_V(th, x/sth, lambda, -1.0, &V0, &V1); + double bessterm = V0 * I0.val + V1 * I1.val; + double besserr = fabs(V0) * I0.err + fabs(V1) * I1.err; + double arg1 = th*lambda; + double sqts = sqrt(th/sth); + int stat_e = gsl_sf_exp_mult_err_e(arg1, 4.0 * GSL_DBL_EPSILON * fabs(arg1), + sqts * bessterm, sqts * besserr, + result); + return GSL_ERROR_SELECT_3(stat_e, stat_V, stat_I); + } + else { + double sh = sqrt(x-1.0)*sqrt(x+1.0); /* sinh(xi) */ + double xi = log(x + sh); /* xi = acosh(x) */ + gsl_sf_result J0, J1; + int stat_J0 = gsl_sf_bessel_J0_e(xi * lambda, &J0); + int stat_J1 = gsl_sf_bessel_J1_e(xi * lambda, &J1); + int stat_J = GSL_ERROR_SELECT_2(stat_J0, stat_J1); + int stat_V = conicalP_0_V(xi, x/sh, lambda, 1.0, &V0, &V1); + double bessterm = V0 * J0.val + V1 * J1.val; + double besserr = fabs(V0) * J0.err + fabs(V1) * J1.err; + double pre_val = sqrt(xi/sh); + double pre_err = 2.0 * fabs(pre_val); + result->val = pre_val * bessterm; + result->err = pre_val * besserr; + result->err += pre_err * fabs(bessterm); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return GSL_ERROR_SELECT_2(stat_V, stat_J); + } + } +} + + +/* P^1_{-1/2 + I lambda} + */ +int +gsl_sf_conicalP_1_e(const double lambda, const double x, gsl_sf_result * result) +{ + /* CHECK_POINTER(result) */ + + if(x <= -1.0) { + DOMAIN_ERROR(result); + } + else if(lambda == 0.0) { + gsl_sf_result K, E; + int stat_K, stat_E; + if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else if(x < 1.0) { + if(1.0-x < GSL_SQRT_DBL_EPSILON) { + double err_amp = GSL_MAX_DBL(1.0, 1.0/(GSL_DBL_EPSILON + fabs(1.0-x))); + result->val = 0.25/M_SQRT2 * sqrt(1.0-x) * (1.0 + 5.0/16.0 * (1.0-x)); + result->err = err_amp * 3.0 * GSL_DBL_EPSILON * fabs(result->val); + return GSL_SUCCESS; + } + else { + const double th = acos(x); + const double s = sin(0.5*th); + const double c2 = 1.0 - s*s; + const double sth = sin(th); + const double pre = 2.0/(M_PI*sth); + stat_K = gsl_sf_ellint_Kcomp_e(s, GSL_MODE_DEFAULT, &K); + stat_E = gsl_sf_ellint_Ecomp_e(s, GSL_MODE_DEFAULT, &E); + result->val = pre * (E.val - c2 * K.val); + result->err = pre * (E.err + fabs(c2) * K.err); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_K; + } + } + else { + if(x-1.0 < GSL_SQRT_DBL_EPSILON) { + double err_amp = GSL_MAX_DBL(1.0, 1.0/(GSL_DBL_EPSILON + fabs(1.0-x))); + result->val = -0.25/M_SQRT2 * sqrt(x-1.0) * (1.0 - 5.0/16.0 * (x-1.0)); + result->err = err_amp * 3.0 * GSL_DBL_EPSILON * fabs(result->val); + return GSL_SUCCESS; + } + else { + const double xi = acosh(x); + const double c = cosh(0.5*xi); + const double t = tanh(0.5*xi); + const double sxi = sinh(xi); + const double pre = 2.0/(M_PI*sxi) * c; + stat_K = gsl_sf_ellint_Kcomp_e(t, GSL_MODE_DEFAULT, &K); + stat_E = gsl_sf_ellint_Ecomp_e(t, GSL_MODE_DEFAULT, &E); + result->val = pre * (E.val - K.val); + result->err = pre * (E.err + K.err); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_K; + } + } + } + else if( (x <= 0.0 && lambda < 1000.0) + || (x < 0.1 && lambda < 17.0) + || (x < 0.2 && lambda < 5.0 ) + ) { + return conicalP_xlt1_hyperg_A(1.0, lambda, x, result); + } + else if( (x <= 0.2 && lambda < 17.0) + || (x < 1.5 && lambda < 20.0) + ) { + const double arg = fabs(x*x - 1.0); + const double sgn = GSL_SIGN(1.0 - x); + const double pre = 0.5*(lambda*lambda + 0.25) * sgn * sqrt(arg); + gsl_sf_result F; + int stat_F = gsl_sf_hyperg_2F1_conj_e(1.5, lambda, 2.0, (1.0-x)/2, &F); + result->val = pre * F.val; + result->err = fabs(pre) * F.err; + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_F; + } + else if(1.5 <= x && lambda < GSL_MAX(x,20.0)) { + gsl_sf_result P; + double lm; + int stat_P = gsl_sf_conicalP_large_x_e(1.0, lambda, x, + &P, &lm + ); + int stat_e = gsl_sf_exp_mult_err_e(lm, 2.0 * GSL_DBL_EPSILON * fabs(lm), + P.val, P.err, + result); + return GSL_ERROR_SELECT_2(stat_e, stat_P); + } + else { + double V0, V1; + if(x < 1.0) { + const double sqrt_1mx = sqrt(1.0 - x); + const double sqrt_1px = sqrt(1.0 + x); + const double th = acos(x); + const double sth = sqrt_1mx * sqrt_1px; /* sin(th) */ + gsl_sf_result I0, I1; + int stat_I0 = gsl_sf_bessel_I0_scaled_e(th * lambda, &I0); + int stat_I1 = gsl_sf_bessel_I1_scaled_e(th * lambda, &I1); + int stat_I = GSL_ERROR_SELECT_2(stat_I0, stat_I1); + int stat_V = conicalP_1_V(th, x/sth, lambda, -1.0, &V0, &V1); + double bessterm = V0 * I0.val + V1 * I1.val; + double besserr = fabs(V0) * I0.err + fabs(V1) * I1.err + + 2.0 * GSL_DBL_EPSILON * fabs(V0 * I0.val) + + 2.0 * GSL_DBL_EPSILON * fabs(V1 * I1.val); + double arg1 = th * lambda; + double sqts = sqrt(th/sth); + int stat_e = gsl_sf_exp_mult_err_e(arg1, 2.0 * GSL_DBL_EPSILON * fabs(arg1), + sqts * bessterm, sqts * besserr, + result); + result->err *= 1.0/sqrt_1mx; + return GSL_ERROR_SELECT_3(stat_e, stat_V, stat_I); + } + else { + const double sqrt_xm1 = sqrt(x - 1.0); + const double sqrt_xp1 = sqrt(x + 1.0); + const double sh = sqrt_xm1 * sqrt_xp1; /* sinh(xi) */ + const double xi = log(x + sh); /* xi = acosh(x) */ + const double xi_lam = xi * lambda; + gsl_sf_result J0, J1; + const int stat_J0 = gsl_sf_bessel_J0_e(xi_lam, &J0); + const int stat_J1 = gsl_sf_bessel_J1_e(xi_lam, &J1); + const int stat_J = GSL_ERROR_SELECT_2(stat_J0, stat_J1); + const int stat_V = conicalP_1_V(xi, x/sh, lambda, 1.0, &V0, &V1); + const double bessterm = V0 * J0.val + V1 * J1.val; + const double besserr = fabs(V0) * J0.err + fabs(V1) * J1.err + + 512.0 * 2.0 * GSL_DBL_EPSILON * fabs(V0 * J0.val) + + 512.0 * 2.0 * GSL_DBL_EPSILON * fabs(V1 * J1.val) + + GSL_DBL_EPSILON * fabs(xi_lam * V0 * J1.val) + + GSL_DBL_EPSILON * fabs(xi_lam * V1 * J0.val); + const double pre = sqrt(xi/sh); + result->val = pre * bessterm; + result->err = pre * besserr * sqrt_xp1 / sqrt_xm1; + result->err += 4.0 * GSL_DBL_EPSILON * fabs(result->val); + return GSL_ERROR_SELECT_2(stat_V, stat_J); + } + } +} + + +/* P^{1/2}_{-1/2 + I lambda} (x) + * [Abramowitz+Stegun 8.6.8, 8.6.12] + * checked OK [GJ] Fri May 8 12:24:36 MDT 1998 + */ +int gsl_sf_conicalP_half_e(const double lambda, const double x, + gsl_sf_result * result + ) +{ + /* CHECK_POINTER(result) */ + + if(x <= -1.0) { + DOMAIN_ERROR(result); + } + else if(x < 1.0) { + double err_amp = 1.0 + 1.0/(GSL_DBL_EPSILON + fabs(1.0-fabs(x))); + double ac = acos(x); + double den = sqrt(sqrt(1.0-x)*sqrt(1.0+x)); + result->val = Root_2OverPi_ / den * cosh(ac * lambda); + result->err = err_amp * 3.0 * GSL_DBL_EPSILON * fabs(result->val); + result->err *= fabs(ac * lambda) + 1.0; + return GSL_SUCCESS; + } + else if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else { + /* x > 1 */ + double err_amp = 1.0 + 1.0/(GSL_DBL_EPSILON + fabs(1.0-fabs(x))); + double sq_term = sqrt(x-1.0)*sqrt(x+1.0); + double ln_term = log(x + sq_term); + double den = sqrt(sq_term); + double carg_val = lambda * ln_term; + double carg_err = 2.0 * GSL_DBL_EPSILON * fabs(carg_val); + gsl_sf_result cos_result; + int stat_cos = gsl_sf_cos_err_e(carg_val, carg_err, &cos_result); + result->val = Root_2OverPi_ / den * cos_result.val; + result->err = err_amp * Root_2OverPi_ / den * cos_result.err; + result->err += 4.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_cos; + } +} + + +/* P^{-1/2}_{-1/2 + I lambda} (x) + * [Abramowitz+Stegun 8.6.9, 8.6.14] + * checked OK [GJ] Fri May 8 12:24:43 MDT 1998 + */ +int gsl_sf_conicalP_mhalf_e(const double lambda, const double x, gsl_sf_result * result) +{ + /* CHECK_POINTER(result) */ + + if(x <= -1.0) { + DOMAIN_ERROR(result); + } + else if(x < 1.0) { + double ac = acos(x); + double den = sqrt(sqrt(1.0-x)*sqrt(1.0+x)); + double arg = ac * lambda; + double err_amp = 1.0 + 1.0/(GSL_DBL_EPSILON + fabs(1.0-fabs(x))); + if(fabs(arg) < GSL_SQRT_DBL_EPSILON) { + result->val = Root_2OverPi_ / den * ac; + result->err = 2.0 * GSL_DBL_EPSILON * fabs(result->val); + result->err *= err_amp; + } + else { + result->val = Root_2OverPi_ / (den*lambda) * sinh(arg); + result->err = GSL_DBL_EPSILON * (fabs(arg)+1.0) * fabs(result->val); + result->err *= err_amp; + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + } + return GSL_SUCCESS; + } + else if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else { + /* x > 1 */ + double sq_term = sqrt(x-1.0)*sqrt(x+1.0); + double ln_term = log(x + sq_term); + double den = sqrt(sq_term); + double arg_val = lambda * ln_term; + double arg_err = 2.0 * GSL_DBL_EPSILON * fabs(arg_val); + if(arg_val < GSL_SQRT_DBL_EPSILON) { + result->val = Root_2OverPi_ / den * ln_term; + result->err = 2.0 * GSL_DBL_EPSILON * fabs(result->val); + return GSL_SUCCESS; + } + else { + gsl_sf_result sin_result; + int stat_sin = gsl_sf_sin_err_e(arg_val, arg_err, &sin_result); + result->val = Root_2OverPi_ / (den*lambda) * sin_result.val; + result->err = Root_2OverPi_ / fabs(den*lambda) * sin_result.err; + result->err += 3.0 * GSL_DBL_EPSILON * fabs(result->val); + return stat_sin; + } + } +} + + +int gsl_sf_conicalP_sph_reg_e(const int l, const double lambda, + const double x, + gsl_sf_result * result + ) +{ + /* CHECK_POINTER(result) */ + + if(x <= -1.0 || l < -1) { + DOMAIN_ERROR(result); + } + else if(l == -1) { + return gsl_sf_conicalP_half_e(lambda, x, result); + } + else if(l == 0) { + return gsl_sf_conicalP_mhalf_e(lambda, x, result); + } + else if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else if(x < 0.0) { + double c = 1.0/sqrt(1.0-x*x); + gsl_sf_result r_Pellm1; + gsl_sf_result r_Pell; + int stat_0 = gsl_sf_conicalP_half_e(lambda, x, &r_Pellm1); /* P^( 1/2) */ + int stat_1 = gsl_sf_conicalP_mhalf_e(lambda, x, &r_Pell); /* P^(-1/2) */ + int stat_P = GSL_ERROR_SELECT_2(stat_0, stat_1); + double Pellm1 = r_Pellm1.val; + double Pell = r_Pell.val; + double Pellp1; + int ell; + + for(ell=0; ell<l; ell++) { + double d = (ell+1.0)*(ell+1.0) + lambda*lambda; + Pellp1 = (Pellm1 - (2.0*ell+1.0)*c*x * Pell) / d; + Pellm1 = Pell; + Pell = Pellp1; + } + + result->val = Pell; + result->err = (0.5*l + 1.0) * GSL_DBL_EPSILON * fabs(Pell); + result->err += GSL_DBL_EPSILON * l * fabs(result->val); + return stat_P; + } + else if(x < 1.0) { + const double xi = x/(sqrt(1.0-x)*sqrt(1.0+x)); + gsl_sf_result rat; + gsl_sf_result Phf; + int stat_CF1 = conicalP_negmu_xlt1_CF1(0.5, l, lambda, x, &rat); + int stat_Phf = gsl_sf_conicalP_half_e(lambda, x, &Phf); + double Pellp1 = rat.val * GSL_SQRT_DBL_MIN; + double Pell = GSL_SQRT_DBL_MIN; + double Pellm1; + int ell; + + for(ell=l; ell>=0; ell--) { + double d = (ell+1.0)*(ell+1.0) + lambda*lambda; + Pellm1 = (2.0*ell+1.0)*xi * Pell + d * Pellp1; + Pellp1 = Pell; + Pell = Pellm1; + } + + result->val = GSL_SQRT_DBL_MIN * Phf.val / Pell; + result->err = GSL_SQRT_DBL_MIN * Phf.err / fabs(Pell); + result->err += fabs(rat.err/rat.val) * (l + 1.0) * fabs(result->val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + + return GSL_ERROR_SELECT_2(stat_Phf, stat_CF1); + } + else if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else { + /* x > 1.0 */ + + const double xi = x/sqrt((x-1.0)*(x+1.0)); + gsl_sf_result rat; + int stat_CF1 = conicalP_negmu_xgt1_CF1(0.5, l, lambda, x, &rat); + int stat_P; + double Pellp1 = rat.val * GSL_SQRT_DBL_MIN; + double Pell = GSL_SQRT_DBL_MIN; + double Pellm1; + int ell; + + for(ell=l; ell>=0; ell--) { + double d = (ell+1.0)*(ell+1.0) + lambda*lambda; + Pellm1 = (2.0*ell+1.0)*xi * Pell - d * Pellp1; + Pellp1 = Pell; + Pell = Pellm1; + } + + if(fabs(Pell) > fabs(Pellp1)){ + gsl_sf_result Phf; + stat_P = gsl_sf_conicalP_half_e(lambda, x, &Phf); + result->val = GSL_SQRT_DBL_MIN * Phf.val / Pell; + result->err = 2.0 * GSL_SQRT_DBL_MIN * Phf.err / fabs(Pell); + result->err += 2.0 * fabs(rat.err/rat.val) * (l + 1.0) * fabs(result->val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + } + else { + gsl_sf_result Pmhf; + stat_P = gsl_sf_conicalP_mhalf_e(lambda, x, &Pmhf); + result->val = GSL_SQRT_DBL_MIN * Pmhf.val / Pellp1; + result->err = 2.0 * GSL_SQRT_DBL_MIN * Pmhf.err / fabs(Pellp1); + result->err += 2.0 * fabs(rat.err/rat.val) * (l + 1.0) * fabs(result->val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + } + + return GSL_ERROR_SELECT_2(stat_P, stat_CF1); + } +} + + +int gsl_sf_conicalP_cyl_reg_e(const int m, const double lambda, + const double x, + gsl_sf_result * result + ) +{ + /* CHECK_POINTER(result) */ + + if(x <= -1.0 || m < -1) { + DOMAIN_ERROR(result); + } + else if(m == -1) { + return gsl_sf_conicalP_1_e(lambda, x, result); + } + else if(m == 0) { + return gsl_sf_conicalP_0_e(lambda, x, result); + } + else if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else if(x < 0.0) { + double c = 1.0/sqrt(1.0-x*x); + gsl_sf_result r_Pkm1; + gsl_sf_result r_Pk; + int stat_0 = gsl_sf_conicalP_1_e(lambda, x, &r_Pkm1); /* P^1 */ + int stat_1 = gsl_sf_conicalP_0_e(lambda, x, &r_Pk); /* P^0 */ + int stat_P = GSL_ERROR_SELECT_2(stat_0, stat_1); + double Pkm1 = r_Pkm1.val; + double Pk = r_Pk.val; + double Pkp1; + int k; + + for(k=0; k<m; k++) { + double d = (k+0.5)*(k+0.5) + lambda*lambda; + Pkp1 = (Pkm1 - 2.0*k*c*x * Pk) / d; + Pkm1 = Pk; + Pk = Pkp1; + } + + result->val = Pk; + result->err = (m + 2.0) * GSL_DBL_EPSILON * fabs(Pk); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + + return stat_P; + } + else if(x < 1.0) { + const double xi = x/(sqrt(1.0-x)*sqrt(1.0+x)); + gsl_sf_result rat; + gsl_sf_result P0; + int stat_CF1 = conicalP_negmu_xlt1_CF1(0.0, m, lambda, x, &rat); + int stat_P0 = gsl_sf_conicalP_0_e(lambda, x, &P0); + double Pkp1 = rat.val * GSL_SQRT_DBL_MIN; + double Pk = GSL_SQRT_DBL_MIN; + double Pkm1; + int k; + + for(k=m; k>0; k--) { + double d = (k+0.5)*(k+0.5) + lambda*lambda; + Pkm1 = 2.0*k*xi * Pk + d * Pkp1; + Pkp1 = Pk; + Pk = Pkm1; + } + + result->val = GSL_SQRT_DBL_MIN * P0.val / Pk; + result->err = 2.0 * GSL_SQRT_DBL_MIN * P0.err / fabs(Pk); + result->err += 2.0 * fabs(rat.err/rat.val) * (m + 1.0) * fabs(result->val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + + return GSL_ERROR_SELECT_2(stat_P0, stat_CF1); + } + else if(x == 1.0) { + result->val = 0.0; + result->err = 0.0; + return GSL_SUCCESS; + } + else { + /* x > 1.0 */ + + const double xi = x/sqrt((x-1.0)*(x+1.0)); + gsl_sf_result rat; + int stat_CF1 = conicalP_negmu_xgt1_CF1(0.0, m, lambda, x, &rat); + int stat_P; + double Pkp1 = rat.val * GSL_SQRT_DBL_MIN; + double Pk = GSL_SQRT_DBL_MIN; + double Pkm1; + int k; + + for(k=m; k>-1; k--) { + double d = (k+0.5)*(k+0.5) + lambda*lambda; + Pkm1 = 2.0*k*xi * Pk - d * Pkp1; + Pkp1 = Pk; + Pk = Pkm1; + } + + if(fabs(Pk) > fabs(Pkp1)){ + gsl_sf_result P1; + stat_P = gsl_sf_conicalP_1_e(lambda, x, &P1); + result->val = GSL_SQRT_DBL_MIN * P1.val / Pk; + result->err = 2.0 * GSL_SQRT_DBL_MIN * P1.err / fabs(Pk); + result->err += 2.0 * fabs(rat.err/rat.val) * (m+2.0) * fabs(result->val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + } + else { + gsl_sf_result P0; + stat_P = gsl_sf_conicalP_0_e(lambda, x, &P0); + result->val = GSL_SQRT_DBL_MIN * P0.val / Pkp1; + result->err = 2.0 * GSL_SQRT_DBL_MIN * P0.err / fabs(Pkp1); + result->err += 2.0 * fabs(rat.err/rat.val) * (m+2.0) * fabs(result->val); + result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); + } + + return GSL_ERROR_SELECT_2(stat_P, stat_CF1); + } +} + + +/*-*-*-*-*-*-*-*-*-* Functions w/ Natural Prototypes *-*-*-*-*-*-*-*-*-*-*/ + +#include "eval.h" + +double gsl_sf_conicalP_0(const double lambda, const double x) +{ + EVAL_RESULT(gsl_sf_conicalP_0_e(lambda, x, &result)); +} + +double gsl_sf_conicalP_1(const double lambda, const double x) +{ + EVAL_RESULT(gsl_sf_conicalP_1_e(lambda, x, &result)); +} + +double gsl_sf_conicalP_half(const double lambda, const double x) +{ + EVAL_RESULT(gsl_sf_conicalP_half_e(lambda, x, &result)); +} + +double gsl_sf_conicalP_mhalf(const double lambda, const double x) +{ + EVAL_RESULT(gsl_sf_conicalP_mhalf_e(lambda, x, &result)); +} + +double gsl_sf_conicalP_sph_reg(const int l, const double lambda, const double x) +{ + EVAL_RESULT(gsl_sf_conicalP_sph_reg_e(l, lambda, x, &result)); +} + +double gsl_sf_conicalP_cyl_reg(const int m, const double lambda, const double x) +{ + EVAL_RESULT(gsl_sf_conicalP_cyl_reg_e(m, lambda, x, &result)); +} |