From d345541af73931219d78eba8cb5c72fe99607f12 Mon Sep 17 00:00:00 2001
From: Lew Rossman <LRossman@outlook.com>
Date: Wed, 10 Sep 2025 11:06:05 -0400
Subject: [PATCH] Avoid possible NAN in leakage.c

---
 src/leakage.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/src/leakage.c b/src/leakage.c
index 048f8d3..a21a9be 100644
--- a/src/leakage.c
+++ b/src/leakage.c
@@ -7,7 +7,7 @@
  Authors:      see AUTHORS
  Copyright:    see AUTHORS
  License:      see LICENSE
- Last Updated: 06/14/2024
+ Last Updated: 09/10/2025
  ******************************************************************************
 */
 /*
@@ -432,15 +432,18 @@ int leakagehasconverged(Project *pr)
         
         // Directly compute a reference leakage at this pressure head
         qref = 0.0;
-        // Contribution from pipes with fixed area leaks
-        if (hyd->Leakage[i].cfa > 0.0)
-            qref = sqrt(h / hyd->Leakage[i].cfa);
-        // Contribution from pipes with variable area leaks
-        if (hyd->Leakage[i].cva > 0.0)
-            qref += pow((h / hyd->Leakage[i].cva), 1.5);
+        if ( h > 0.0)
+        {
+            // Contribution from pipes with fixed area leaks
+            if (hyd->Leakage[i].cfa > 0.0)
+                qref = sqrt(h / hyd->Leakage[i].cfa);
+            // Contribution from pipes with variable area leaks
+            if (hyd->Leakage[i].cva > 0.0)
+                qref += pow((h / hyd->Leakage[i].cva), 1.5);
+        }
         
         // Compare reference leakage to solution leakage
-        qtest = hyd->Leakage[i].qfa + hyd->Leakage[i].qva;
+        qtest = hyd->Leakage[i].qfa + hyd->Leakage[i].qva;        
         if (fabs(qref - qtest) > QTOL) return FALSE;
     }
     return TRUE;