Index: /issm/trunk-jpl/src/m/classes/stochasticforcing.py
===================================================================
--- /issm/trunk-jpl/src/m/classes/stochasticforcing.py	(revision 26670)
+++ /issm/trunk-jpl/src/m/classes/stochasticforcing.py	(revision 26671)
@@ -108,5 +108,5 @@
         if (checkdefaults):
             md = checkfield(md, 'fieldname', 'stochasticforcing.defaultdimension', 'numel', 1, 'NaN', 1, 'Inf', 1, '>', 0)
-            md = checkfield(md, 'fieldname', 'stochasticforcing.default_id', 'Inf', 1, '>=', 0, '<=', self.defaultdimension, 'size', [md.mesh.numberofelements])
+            md = checkfield(md, 'fieldname', 'stochasticforcing.default_id','Inf',1,'NaN',1,'>=',0,'<=',self.defaultdimension,'size', [md.mesh.numberofelements])
         return md
     # }}}
@@ -145,5 +145,5 @@
                         tempcovariance[:, col] = 1 / yts * tempcovariance[:, col]
             # Set dummy default_id vector if defaults not used
-            if np.isnan(self.default_id):
+            if np.any(np.isnan(self.default_id)):
                 self.default_id = np.zeros(md.mesh.numberofelements)
             WriteData(fid, prefix, 'data', num_fields, 'name', 'md.stochasticforcing.num_fields', 'format', 'Integer')