3 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 2007 Brian Gough
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 3 of the License, or (at
8 * your option) any later version.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 #include <gsl/gsl_integration.h>
23 /* Gauss quadrature weights and kronrod quadrature abscissae and
24 weights as evaluated with 80 decimal digit arithmetic by
25 L. W. Fullerton, Bell Labs, Nov. 1981. */
27 static const double xgk[11] = /* abscissae of the 21-point kronrod rule */
29 0.995657163025808080735527280689003,
30 0.973906528517171720077964012084452,
31 0.930157491355708226001207180059508,
32 0.865063366688984510732096688423493,
33 0.780817726586416897063717578345042,
34 0.679409568299024406234327365114874,
35 0.562757134668604683339000099272694,
36 0.433395394129247190799265943165784,
37 0.294392862701460198131126603103866,
38 0.148874338981631210884826001129720,
39 0.000000000000000000000000000000000
42 /* xgk[1], xgk[3], ... abscissae of the 10-point gauss rule.
43 xgk[0], xgk[2], ... abscissae to optimally extend the 10-point gauss rule */
45 static const double wg[5] = /* weights of the 10-point gauss rule */
47 0.066671344308688137593568809893332,
48 0.149451349150580593145776339657697,
49 0.219086362515982043995534934228163,
50 0.269266719309996355091226921569469,
51 0.295524224714752870173892994651338
54 static const double wgk[11] = /* weights of the 21-point kronrod rule */
56 0.011694638867371874278064396062192,
57 0.032558162307964727478818972459390,
58 0.054755896574351996031381300244580,
59 0.075039674810919952767043140916190,
60 0.093125454583697605535065465083366,
61 0.109387158802297641899210590325805,
62 0.123491976262065851077958109831074,
63 0.134709217311473325928054001771707,
64 0.142775938577060080797094273138717,
65 0.147739104901338491374841515972068,
66 0.149445554002916905664936468389821
71 gsl_integration_qk21 (const gsl_function * f, double a, double b,
72 double *result, double *abserr,
73 double *resabs, double *resasc)
75 double fv1[11], fv2[11];
76 gsl_integration_qk (11, xgk, wg, wgk, fv1, fv2, f, a, b, result, abserr, resabs, resasc);