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/* integration/util.c
*
* Copyright (C) 1996, 1997, 1998, 1999, 2000 Brian Gough
*
* 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.
*/
static inline
void update (gsl_integration_workspace * workspace,
double a1, double b1, double area1, double error1,
double a2, double b2, double area2, double error2);
static inline void
retrieve (const gsl_integration_workspace * workspace,
double * a, double * b, double * r, double * e);
static inline
void update (gsl_integration_workspace * workspace,
double a1, double b1, double area1, double error1,
double a2, double b2, double area2, double error2)
{
double * alist = workspace->alist ;
double * blist = workspace->blist ;
double * rlist = workspace->rlist ;
double * elist = workspace->elist ;
size_t * level = workspace->level ;
const size_t i_max = workspace->i ;
const size_t i_new = workspace->size ;
const size_t new_level = workspace->level[i_max] + 1;
/* append the newly-created intervals to the list */
if (error2 > error1)
{
alist[i_max] = a2; /* blist[maxerr] is already == b2 */
rlist[i_max] = area2;
elist[i_max] = error2;
level[i_max] = new_level;
alist[i_new] = a1;
blist[i_new] = b1;
rlist[i_new] = area1;
elist[i_new] = error1;
level[i_new] = new_level;
}
else
{
blist[i_max] = b1; /* alist[maxerr] is already == a1 */
rlist[i_max] = area1;
elist[i_max] = error1;
level[i_max] = new_level;
alist[i_new] = a2;
blist[i_new] = b2;
rlist[i_new] = area2;
elist[i_new] = error2;
level[i_new] = new_level;
}
workspace->size++;
if (new_level > workspace->maximum_level)
{
workspace->maximum_level = new_level;
}
qpsrt (workspace) ;
}
static inline void
retrieve (const gsl_integration_workspace * workspace,
double * a, double * b, double * r, double * e)
{
const size_t i = workspace->i;
double * alist = workspace->alist;
double * blist = workspace->blist;
double * rlist = workspace->rlist;
double * elist = workspace->elist;
*a = alist[i] ;
*b = blist[i] ;
*r = rlist[i] ;
*e = elist[i] ;
}
static inline double
sum_results (const gsl_integration_workspace * workspace);
static inline double
sum_results (const gsl_integration_workspace * workspace)
{
const double * const rlist = workspace->rlist ;
const size_t n = workspace->size;
size_t k;
double result_sum = 0;
for (k = 0; k < n; k++)
{
result_sum += rlist[k];
}
return result_sum;
}
static inline int
subinterval_too_small (double a1, double a2, double b2);
static inline int
subinterval_too_small (double a1, double a2, double b2)
{
const double e = GSL_DBL_EPSILON;
const double u = GSL_DBL_MIN;
double tmp = (1 + 100 * e) * (fabs (a2) + 1000 * u);
int status = fabs (a1) <= tmp && fabs (b2) <= tmp;
return status;
}