Introduced a converting function form AssignmentCollection to NodeCollection.

pystencils/node_collection.py

@@ -6,9 +6,10 @@ import sympy as sp
 from sympy.codegen import Assignment
 from sympy.codegen.rewriting import ReplaceOptim, optimize
 
-from pystencils.astnodes import Block, Node
+from pystencils.astnodes import Block, Node, SympyAssignment
 from pystencils.backends.cbackend import CustomCodeNode
 from pystencils.functions import DivFunc
+from pystencils.simp import AssignmentCollection
 
 
 class NodeCollection:
@@ -28,6 +29,10 @@ class NodeCollection:
 
         self.simplification_hints = {}
 
+    @staticmethod
+    def from_assignment_collection(assignment_collection: AssignmentCollection):
+        return NodeCollection([SympyAssignment(a.lhs, a.rhs) for a in assignment_collection.all_assignments])
+
     def evaluate_terms(self):
         evaluate_constant_terms = ReplaceOptim(
             lambda e: hasattr(e, 'is_constant') and e.is_constant and not e.is_integer,

pystencils_tests/test_nodecollection.py

+import sympy as sp
+
+from pystencils import AssignmentCollection, Assignment
+from pystencils.node_collection import NodeCollection
+from pystencils.astnodes import SympyAssignment
+
+
+def test_node_collection_from_assignment_collection():
+    x = sp.symbols('x')
+    assignment_collection = AssignmentCollection([Assignment(x, 2)])
+    node_collection = NodeCollection.from_assignment_collection(assignment_collection)
+
+    assert node_collection.all_assignments[0] == SympyAssignment(x, 2)