Physics metrics updated for power grid use case to return 0 when no v…

…iolation (#40)

lips/metrics/power_grid/physics_compliances.py

@@ -55,8 +55,8 @@ def verify_current_pos(predictions: dict,
         except KeyError:
             logger.error("%s does not exists in predictions dict", key_)
             raise
+        verifications[key_] = {}
         if np.any(a_arr < 0):
-            verifications[key_] = {}
             a_or_errors = np.array(np.where(a_arr < 0)).T
             a_or_violation_proportion = (1.0 * len(a_or_errors)) / a_arr.size
             error_a_or = -np.sum(np.minimum(a_arr.flatten(), 0.))
@@ -67,6 +67,7 @@ def verify_current_pos(predictions: dict,
             verifications[key_]["Violation_proportion"] = float(a_or_violation_proportion)
         else:
             logger.info("Current positivity check passed for %s", key_)
+            verifications[key_]["Violation_proportion"] = 0.
     return verifications
 
 def verify_voltage_pos(predictions:dict,
@@ -101,8 +102,8 @@ def verify_voltage_pos(predictions:dict,
         except KeyError:
             logger.error("%s does not exists in predictions dict", key_)
             raise
+        verifications[key_] = {}
         if np.any(v_arr < 0):
-            verifications[key_] = {}
             v_or_errors = np.array(np.where(v_arr < 0)).T
             v_or_violation_proportion = len(v_or_errors) / v_arr.size
             error_v_or = -np.sum(np.minimum(v_arr.flatten(), 0.))
@@ -113,6 +114,7 @@ def verify_voltage_pos(predictions:dict,
             verifications[key_]["Violation_proportion"] = float(v_or_violation_proportion)
         else:
             logger.info("Voltage positivity check passed for %s", key_)
+            verifications[key_]["Violation_proportion"] = 0.
     return verifications
 
 def verify_loss_pos(predictions: dict,
@@ -159,6 +161,7 @@ def verify_loss_pos(predictions: dict,
         verifications["violation_proportion"] = float(loss_violation_proportion)
     else:
         logger.info("Loss positivity check passed")
+        verifications["violation_proportion"] = 0.
     return verifications
 
 def verify_disc_lines(predictions: dict,