feat: template no_feature_coordinates

Author: FunMelon

openevolve/prompt/sampler.py

@@ -205,11 +205,13 @@ def _identify_improvement_areas(
         # Note feature exploration (not good/bad, just informational)
         if feature_dimensions:
             feature_coords = format_feature_coordinates(metrics, feature_dimensions)
-            if feature_coords != "No feature coordinates":
+            if feature_coords == "":
+                msg = self.template_manager.get_fragment("no_feature_coordinates")
+            else:
                 msg = self.template_manager.get_fragment(
                     "exploring_region", features=feature_coords
                 )
-                improvement_areas.append(msg)
+            improvement_areas.append(msg)
 
         # Code length check (configurable threshold)
         threshold = (

openevolve/prompts/defaults/fragments.json

@@ -14,5 +14,6 @@
   "metrics_improved": "Metrics showing improvement: {metrics}. Consider continuing with similar approaches.",
   "metrics_regressed": "Metrics showing changes: {metrics}. Consider different approaches in these areas.",
   "code_simplification": "Consider simplifying the code to improve readability and maintainability",
-  "default_improvement": "Focus on improving the fitness score while exploring diverse solutions"
+  "default_improvement": "Focus on improving the fitness score while exploring diverse solutions",
+  "no_feature_coordinates": "No feature coordinates"
 }

openevolve/utils/metrics_utils.py

@@ -139,7 +139,7 @@ def format_feature_coordinates(metrics: Dict[str, Any], feature_dimensions: List
             else:
                 feature_values.append(f"{dim}={value}")
 
-    if not feature_values:
-        return "No feature coordinates"
+    if not feature_values:  # No valid feature coordinates found will return empty string
+        return ""
 
     return ", ".join(feature_values)