From 5729a29636c6c7e29ab0ad22792bdf5d8963447c Mon Sep 17 00:00:00 2001
From: Chris Keckler <keckler@berkeley.edu>
Date: Tue, 28 Sep 2021 14:13:04 -0500
Subject: [PATCH] Fix applyInputParams bug when values are zero (#425)

---
 armi/materials/b4c.py          |  2 +-
 armi/materials/mox.py          | 19 ++++++++++++++++---
 armi/materials/sulfur.py       |  2 +-
 armi/materials/thU.py          |  2 +-
 armi/materials/uraniumOxide.py | 10 ++++++++--
 5 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/armi/materials/b4c.py b/armi/materials/b4c.py
index 63c71d30c..e63146d9d 100644
--- a/armi/materials/b4c.py
+++ b/armi/materials/b4c.py
@@ -29,7 +29,7 @@ class B4C(material.Material):
     def applyInputParams(
         self, B10_wt_frac=None, theoretical_density=None, *args, **kwargs
     ):
-        if B10_wt_frac:
+        if B10_wt_frac is not None:
             # we can't just use the generic enrichment adjustment here because the
             # carbon has to change with enrich.
             self.adjustMassEnrichment(B10_wt_frac)
diff --git a/armi/materials/mox.py b/armi/materials/mox.py
index 86cf3551b..ab97f339d 100644
--- a/armi/materials/mox.py
+++ b/armi/materials/mox.py
@@ -46,16 +46,29 @@ class MOX(UraniumOxide):
     def applyInputParams(
         self, U235_wt_frac=None, TD_frac=None, mass_frac_PU02=None, *args, **kwargs
     ):
-        if U235_wt_frac:
+        if U235_wt_frac is not None:
             self.adjustMassEnrichment(U235_wt_frac)
 
         td = TD_frac
-        if td:
+        if td is not None:
+            if td > 1.0:
+                runLog.warning(
+                    "Theoretical density frac for {0} is {1}, which is >1"
+                    "".format(self, td),
+                    single=True,
+                    label="Large theoretical density",
+                )
+            elif td == 0:
+                runLog.warning(
+                    "Theoretical density frac for {self} is zero!",
+                    single=True,
+                    label="Zero theoretical density",
+                )
             self.adjustTD(td)
         else:
             self.adjustTD(1.00)  # default to fully dense.
 
-        if mass_frac_PU02:
+        if mass_frac_PU02 is not None:
             self.setMassFracPuO2(mass_frac_PU02)
         material.FuelMaterial.applyInputParams(self, *args, **kwargs)
 
diff --git a/armi/materials/sulfur.py b/armi/materials/sulfur.py
index 93317f793..f5c69497d 100644
--- a/armi/materials/sulfur.py
+++ b/armi/materials/sulfur.py
@@ -25,7 +25,7 @@ class Sulfur(material.Fluid):
     name = "Sulfur"
 
     def applyInputParams(self, sulfur_density_frac=None):
-        if sulfur_density_frac:
+        if sulfur_density_frac is not None:
             self.fullDensFrac = float(sulfur_density_frac)
 
     def setDefaultMassFracs(self):
diff --git a/armi/materials/thU.py b/armi/materials/thU.py
index f7d88b12e..5d88935f2 100644
--- a/armi/materials/thU.py
+++ b/armi/materials/thU.py
@@ -38,7 +38,7 @@ def getEnrichment(self):
     def applyInputParams(self, U233_wt_frac=None, *args, **kwargs):
         runLog.warning("Material {} has not yet been tested for accuracy".format("ThU"))
 
-        if U233_wt_frac:
+        if U233_wt_frac is not None:
             self.adjustMassEnrichment(U233_wt_frac)
         material.FuelMaterial.applyInputParams(self, *args, **kwargs)
 
diff --git a/armi/materials/uraniumOxide.py b/armi/materials/uraniumOxide.py
index 912bebfdc..c20ef8295 100644
--- a/armi/materials/uraniumOxide.py
+++ b/armi/materials/uraniumOxide.py
@@ -95,11 +95,11 @@ def getTD(self):
         return self.theoreticalDensityFrac
 
     def applyInputParams(self, U235_wt_frac=None, TD_frac=None, *args, **kwargs):
-        if U235_wt_frac:
+        if U235_wt_frac is not None:
             self.adjustMassEnrichment(U235_wt_frac)
 
         td = TD_frac
-        if td:
+        if td is not None:
             if td > 1.0:
                 runLog.warning(
                     "Theoretical density frac for {0} is {1}, which is >1"
@@ -107,6 +107,12 @@ def applyInputParams(self, U235_wt_frac=None, TD_frac=None, *args, **kwargs):
                     single=True,
                     label="Large theoretical density",
                 )
+            elif td == 0:
+                runLog.warning(
+                    "Theoretical density frac for {self} is zero!",
+                    single=True,
+                    label="Zero theoretical density",
+                )
             self.adjustTD(td)
         else:
             self.adjustTD(1.00)  # default to fully dense.