Improve error msg for beam splitter

src/nodes/beam_splitter.rs

@@ -105,7 +105,7 @@ impl BeamSplitter {
                     s.scale_vertical(1.0 - self.ratio()).unwrap();
                     out1_2_spectrum = Some(s);
                 }
-                _ => return Err(OpossumError::Analysis("expected DataEnergy value".into())),
+                _ => return Err(OpossumError::Analysis("expected DataEnergy value at input port".into())),
             }
         }
         if let Some(Some(in2)) = in2 {
@@ -118,7 +118,7 @@ impl BeamSplitter {
                     s.scale_vertical(1.0 - self.ratio()).unwrap();
                     out2_2_spectrum = Some(s);
                 }
-                _ => return Err(OpossumError::Analysis("expected DataEnergy value".into())),
+                _ => return Err(OpossumError::Analysis("expected DataEnergy value at input port".into())),
             }
         }
         let out1_spec = merge_spectra(out1_1_spectrum, out2_2_spectrum);

src/nodes/group.rs

@@ -355,7 +355,8 @@ impl NodeGroup {
         let g_clone = self.g.0.clone();
         let mut group_srcs = g_clone.externals(Direction::Incoming);
         let mut light_result = LightResult::default();
-        let sorted = toposort(&g_clone, None).unwrap();
+        let sorted = toposort(&self.g.0, None)
+            .map_err(|_| OpossumError::Analysis("topological sort failed".into()))?;
         for idx in sorted {
             // Check if node is group src node
             let incoming_edges = if group_srcs.any(|gs| gs == idx) {