Fix f1 initialization bug in CBF and RBF

src/libnptm/sph_subs.cpp

@@ -123,7 +123,7 @@ void cbf(int n, dcomplex z, int &nm, dcomplex *csj) {
   if (m < n) nm = m;
   else m = msta2(a0, n, 15);
   dcomplex cf0 = 0.0;
-  dcomplex cf1 = 1.0e-100;
+  dcomplex cf1 = 1.0e+00 - 100.0;
   dcomplex cf, cs;
   for (int k = m; k >= 0; k--) {
     cf = (2.0 * k + 3.0) * cf1 / z - cf0;
@@ -668,7 +668,7 @@ void rbf(int n, double x, int &nm, double sj[]) {
   if (m < n) nm = m;
   else m = msta2(a0, n, 15);
   double f0 = 0.0;
-  double f1 = 1.0e-100;
+  double f1 = 1.0e+00 - 100.0;
   double f;
   for (int k = m; k >= 0; k--) {
     f = (2.0 * k +3.0) * f1 / x - f0;