Incorporating changes requested by @giudgiud

src/scattdata.cpp

@@ -38,12 +38,21 @@ ScattData::base_init(int order, const xt::xtensor<int, 1>& in_gmin,
     mult[gin] = in_mult[gin];
 
     // Make sure the multiplicity does not have 0s
+    unsigned long int num_converted = 0;
     for (int go = 0; go < mult[gin].size(); go++) {
       if (mult[gin][go] == 0.) {
+        num_converted += 1;
         mult[gin][go] = 1.;
       }
     }
 
+    if (num_converted > 0) {
+      // Raise a warning to the user if we did have to do the conversion
+      std::string msg = std::to_string(num_converted) +
+           "entries in the Multiplicity Matrix were changed from 0 to 1";
+      warning(msg);
+    }
+
     // Make sure the energy is normalized
     double norm = std::accumulate(energy[gin].begin(), energy[gin].end(), 0.);