1 files changed, 137 insertions, 0 deletions
diff --git a/gsl-1.9/integration/util.c b/gsl-1.9/integration/util.c
new file mode 100644
index 0000000..8be4f64
--- /dev/null
+++ b/gsl-1.9/integration/util.c
@@ -0,0 +1,137 @@
+/* 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;
+}
+