1 files changed, 30 insertions, 0 deletions
diff --git a/gsl-1.9/specfunc/cheb_eval_mode.c b/gsl-1.9/specfunc/cheb_eval_mode.c
new file mode 100644
index 0000000..80127de
--- /dev/null
+++ b/gsl-1.9/specfunc/cheb_eval_mode.c
@@ -0,0 +1,30 @@
+static inline int
+cheb_eval_mode_e(const cheb_series * cs,
+                 const double x,
+                 gsl_mode_t mode,
+                 gsl_sf_result * result)
+{
+  int j;
+  double d  = 0.0;
+  double dd = 0.0;
+
+  double y  = (2.*x - cs->a - cs->b) / (cs->b - cs->a);
+  double y2 = 2.0 * y;
+
+  int eval_order;
+
+  if(GSL_MODE_PREC(mode) == GSL_PREC_DOUBLE)
+    eval_order = cs->order;
+  else
+    eval_order = cs->order_sp;
+
+  for(j = eval_order; j>=1; j--) {
+    double temp = d;
+    d = y2*d - dd + cs->c[j];
+    dd = temp;
+  }
+
+  result->val = y*d - dd + 0.5 * cs->c[0];
+  result->err = GSL_DBL_EPSILON * fabs(result->val) + fabs(cs->c[eval_order]);
+  return GSL_SUCCESS;
+}