Merge branch 'mpi-operators' of gricad-gitlab.univ-grenoble-alpes.fr:keckj/hysop into mpi-operators

hysop/symbolic/relational.py

@@ -142,16 +142,19 @@ class Assignment(BinaryRelation):
         return '='
     
     @classmethod
-    def assign(cls, lhs, rhs):
+    def assign(cls, lhs, rhs, skip_zero_rhs=False):
         exprs = ()
+        def create_expr(rhs):
+            return (not skip_zero_rhs) or (rhs!=0)
         if isinstance(lhs, npw.ndarray) and isinstance(rhs, npw.ndarray):
             assert isinstance(lhs, npw.ndarray), type(lhs)
             assert isinstance(rhs, npw.ndarray), type(rhs)
             assert (rhs.size == lhs.size)
             assert (rhs.shape == lhs.shape)
             for (l,r) in zip(lhs.ravel().tolist(), rhs.ravel().tolist()):
-                e = cls(l, r)
-                exprs += (e,)
+                if create_expr(r):
+                    e = cls(l, r)
+                    exprs += (e,)
         elif isinstance(lhs, npw.ndarray) or isinstance(rhs, npw.ndarray):
             if isinstance(lhs, npw.ndarray):
                 lhss = lhs.ravel().tolist()
@@ -160,13 +163,15 @@ class Assignment(BinaryRelation):
                 rhss = rhs.ravel().tolist()
                 lhss = (lhs,)*len(rhss)
             for (l,r) in zip(lhss, rhss):
-                e = cls(l, r)
-                exprs += (e,)
+                if create_expr(r):
+                    e = cls(l, r)
+                    exprs += (e,)
         elif isinstance(lhs, sm.Basic) and isinstance(rhs, sm.Basic):
             assert isinstance(lhs, sm.Basic), type(lhs)
             assert isinstance(rhs, sm.Basic), type(rhs)
             e = cls(lhs, rhs)
-            exprs += (e,)
+            if create_expr(rhs):
+                exprs += (e,)
         else:
             msg='Cannot handle operand types:\n  *lhs: {}\n  *rhs: {}\n'
             msg=msg.format(type(lhs), type(rhs))