| /* specfunc/dawson.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_sf_dawson.h> |
| |
| #include "error.h" |
| #include "chebyshev.h" |
| #include "cheb_eval.c" |
| |
| /* Based on ddaws.f, Fullerton, W., (LANL) */ |
| |
| |
| /* Chebyshev expansions |
| |
| Series for DAW on the interval 0. to 1.00000E+00 |
| with weighted error 8.95E-32 |
| log weighted error 31.05 |
| significant figures required 30.41 |
| decimal places required 31.71 |
| |
| Series for DAW2 on the interval 0. to 1.60000E+01 |
| with weighted error 1.61E-32 |
| log weighted error 31.79 |
| significant figures required 31.40 |
| decimal places required 32.62 |
| |
| Series for DAWA on the interval 0. to 6.25000E-02 |
| with weighted error 1.97E-32 |
| log weighted error 31.71 |
| significant figures required 29.79 |
| decimal places required 32.64 |
| */ |
| static double daw_data[21] = { |
| -0.6351734375145949201065127736293e-02, |
| -0.2294071479677386939899824125866e+00, |
| 0.2213050093908476441683979161786e-01, |
| -0.1549265453892985046743057753375e-02, |
| 0.8497327715684917456777542948066e-04, |
| -0.3828266270972014924994099521309e-05, |
| 0.1462854806250163197757148949539e-06, |
| -0.4851982381825991798846715425114e-08, |
| 0.1421463577759139790347568183304e-09, |
| -0.3728836087920596525335493054088e-11, |
| 0.8854942961778203370194565231369e-13, |
| -0.1920757131350206355421648417493e-14, |
| 0.3834325867246327588241074439253e-16, |
| -0.7089154168175881633584099327999e-18, |
| 0.1220552135889457674416901120000e-19, |
| -0.1966204826605348760299451733333e-21, |
| 0.2975845541376597189113173333333e-23, |
| -0.4247069514800596951039999999999e-25, |
| 0.5734270767391742798506666666666e-27, |
| -0.7345836823178450261333333333333e-29, |
| 0.8951937667516552533333333333333e-31 |
| }; |
| static cheb_series daw_cs = { |
| daw_data, |
| 15, /* 20, */ |
| -1, 1, |
| 9 |
| }; |
| |
| static double daw2_data[45] = { |
| -0.56886544105215527114160533733674e-01, |
| -0.31811346996168131279322878048822e+00, |
| 0.20873845413642236789741580198858e+00, |
| -0.12475409913779131214073498314784e+00, |
| 0.67869305186676777092847516423676e-01, |
| -0.33659144895270939503068230966587e-01, |
| 0.15260781271987971743682460381640e-01, |
| -0.63483709625962148230586094788535e-02, |
| 0.24326740920748520596865966109343e-02, |
| -0.86219541491065032038526983549637e-03, |
| 0.28376573336321625302857636538295e-03, |
| -0.87057549874170423699396581464335e-04, |
| 0.24986849985481658331800044137276e-04, |
| -0.67319286764160294344603050339520e-05, |
| 0.17078578785573543710504524047844e-05, |
| -0.40917551226475381271896592490038e-06, |
| 0.92828292216755773260751785312273e-07, |
| -0.19991403610147617829845096332198e-07, |
| 0.40963490644082195241210487868917e-08, |
| -0.80032409540993168075706781753561e-09, |
| 0.14938503128761465059143225550110e-09, |
| -0.26687999885622329284924651063339e-10, |
| 0.45712216985159458151405617724103e-11, |
| -0.75187305222043565872243727326771e-12, |
| 0.11893100052629681879029828987302e-12, |
| -0.18116907933852346973490318263084e-13, |
| 0.26611733684358969193001612199626e-14, |
| -0.37738863052129419795444109905930e-15, |
| 0.51727953789087172679680082229329e-16, |
| -0.68603684084077500979419564670102e-17, |
| 0.88123751354161071806469337321745e-18, |
| -0.10974248249996606292106299624652e-18, |
| 0.13261199326367178513595545891635e-19, |
| -0.15562732768137380785488776571562e-20, |
| 0.17751425583655720607833415570773e-21, |
| -0.19695006967006578384953608765439e-22, |
| 0.21270074896998699661924010120533e-23, |
| -0.22375398124627973794182113962666e-24, |
| 0.22942768578582348946971383125333e-25, |
| -0.22943788846552928693329592319999e-26, |
| 0.22391702100592453618342297600000e-27, |
| -0.21338230616608897703678225066666e-28, |
| 0.19866196585123531518028458666666e-29, |
| -0.18079295866694391771955199999999e-30, |
| 0.16090686015283030305450666666666e-31 |
| }; |
| static cheb_series daw2_cs = { |
| daw2_data, |
| 32, /* 44, */ |
| -1, 1, |
| 21 |
| }; |
| |
| static double dawa_data[75] = { |
| 0.1690485637765703755422637438849e-01, |
| 0.8683252278406957990536107850768e-02, |
| 0.2424864042417715453277703459889e-03, |
| 0.1261182399572690001651949240377e-04, |
| 0.1066453314636176955705691125906e-05, |
| 0.1358159794790727611348424505728e-06, |
| 0.2171042356577298398904312744743e-07, |
| 0.2867010501805295270343676804813e-08, |
| -0.1901336393035820112282492378024e-09, |
| -0.3097780484395201125532065774268e-09, |
| -0.1029414876057509247398132286413e-09, |
| -0.6260356459459576150417587283121e-11, |
| 0.8563132497446451216262303166276e-11, |
| 0.3033045148075659292976266276257e-11, |
| -0.2523618306809291372630886938826e-12, |
| -0.4210604795440664513175461934510e-12, |
| -0.4431140826646238312143429452036e-13, |
| 0.4911210272841205205940037065117e-13, |
| 0.1235856242283903407076477954739e-13, |
| -0.5788733199016569246955765071069e-14, |
| -0.2282723294807358620978183957030e-14, |
| 0.7637149411014126476312362917590e-15, |
| 0.3851546883566811728777594002095e-15, |
| -0.1199932056928290592803237283045e-15, |
| -0.6313439150094572347334270285250e-16, |
| 0.2239559965972975375254912790237e-16, |
| 0.9987925830076495995132891200749e-17, |
| -0.4681068274322495334536246507252e-17, |
| -0.1436303644349721337241628751534e-17, |
| 0.1020822731410541112977908032130e-17, |
| 0.1538908873136092072837389822372e-18, |
| -0.2189157877645793888894790926056e-18, |
| 0.2156879197938651750392359152517e-20, |
| 0.4370219827442449851134792557395e-19, |
| -0.8234581460977207241098927905177e-20, |
| -0.7498648721256466222903202835420e-20, |
| 0.3282536720735671610957612930039e-20, |
| 0.8858064309503921116076561515151e-21, |
| -0.9185087111727002988094460531485e-21, |
| 0.2978962223788748988314166045791e-22, |
| 0.1972132136618471883159505468041e-21, |
| -0.5974775596362906638089584995117e-22, |
| -0.2834410031503850965443825182441e-22, |
| 0.2209560791131554514777150489012e-22, |
| -0.5439955741897144300079480307711e-25, |
| -0.5213549243294848668017136696470e-23, |
| 0.1702350556813114199065671499076e-23, |
| 0.6917400860836148343022185660197e-24, |
| -0.6540941793002752512239445125802e-24, |
| 0.6093576580439328960371824654636e-25, |
| 0.1408070432905187461501945080272e-24, |
| -0.6785886121054846331167674943755e-25, |
| -0.9799732036214295711741583102225e-26, |
| 0.2121244903099041332598960939160e-25, |
| -0.5954455022548790938238802154487e-26, |
| -0.3093088861875470177838847232049e-26, |
| 0.2854389216344524682400691986104e-26, |
| -0.3951289447379305566023477271811e-27, |
| -0.5906000648607628478116840894453e-27, |
| 0.3670236964668687003647889980609e-27, |
| -0.4839958238042276256598303038941e-29, |
| -0.9799265984210443869597404017022e-28, |
| 0.4684773732612130606158908804300e-28, |
| 0.5030877696993461051647667603155e-29, |
| -0.1547395051706028239247552068295e-28, |
| 0.6112180185086419243976005662714e-29, |
| 0.1357913399124811650343602736158e-29, |
| -0.2417687752768673088385304299044e-29, |
| 0.8369074582074298945292887587291e-30, |
| 0.2665413042788979165838319401566e-30, |
| -0.3811653692354890336935691003712e-30, |
| 0.1230054721884951464371706872585e-30, |
| 0.4622506399041493508805536929983e-31, |
| -0.6120087296881677722911435593001e-31, |
| 0.1966024640193164686956230217896e-31 |
| }; |
| static cheb_series dawa_cs = { |
| dawa_data, |
| 34, /* 74, */ |
| -1, 1, |
| 12 |
| }; |
| |
| |
| /*-*-*-*-*-*-*-*-*-*-*-* Functions with Error Codes *-*-*-*-*-*-*-*-*-*-*-*/ |
| |
| int |
| gsl_sf_dawson_e(double x, gsl_sf_result * result) |
| { |
| const double xsml = 1.225 * GSL_SQRT_DBL_EPSILON; |
| const double xbig = 1.0/(M_SQRT2*GSL_SQRT_DBL_EPSILON); |
| const double xmax = 0.1 * GSL_DBL_MAX; |
| |
| const double y = fabs(x); |
| |
| if(y < xsml) { |
| result->val = x; |
| result->err = 0.0; |
| return GSL_SUCCESS; |
| } |
| else if(y < 1.0) { |
| gsl_sf_result result_c; |
| cheb_eval_e(&daw_cs, 2.0*y*y - 1.0, &result_c); |
| result->val = x * (0.75 + result_c.val); |
| result->err = y * result_c.err; |
| result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); |
| return GSL_SUCCESS; |
| } |
| else if(y < 4.0) { |
| gsl_sf_result result_c; |
| cheb_eval_e(&daw2_cs, 0.125*y*y - 1.0, &result_c); |
| result->val = x * (0.25 + result_c.val); |
| result->err = y * result_c.err; |
| result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); |
| return GSL_SUCCESS; |
| } |
| else if(y < xbig) { |
| gsl_sf_result result_c; |
| cheb_eval_e(&dawa_cs, 32.0/(y*y) - 1.0, &result_c); |
| result->val = (0.5 + result_c.val) / x; |
| result->err = result_c.err / y; |
| result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val); |
| return GSL_SUCCESS; |
| } |
| else if(y < xmax) { |
| result->val = 0.5/x; |
| result->err = 2.0 * GSL_DBL_EPSILON * result->val; |
| return GSL_SUCCESS; |
| } |
| else { |
| UNDERFLOW_ERROR(result); |
| } |
| } |
| |
| |
| /*-*-*-*-*-*-*-*-*-* Functions w/ Natural Prototypes *-*-*-*-*-*-*-*-*-*-*/ |
| |
| #include "eval.h" |
| |
| double gsl_sf_dawson(double x) |
| { |
| EVAL_RESULT(gsl_sf_dawson_e(x, &result)); |
| } |