grading for vsepr

common/lib/capa/capa/chem/chemtools.py

 from collections import OrderedDict
+import json
 
 
 def vsepr_parse_user_answer(user_input):
-    d = OrderedDict(eval(user_input))
+    d = OrderedDict(json.loads(user_input))
     d['atoms'] = OrderedDict(sorted(d['atoms'].items()))
     return d
 
@@ -10,16 +11,42 @@ def vsepr_parse_user_answer(user_input):
 def vsepr_build_correct_answer(geometry, atoms):
     correct_answer = OrderedDict()
     correct_answer['geometry'] = geometry
-    correct_answer['atoms'] = OrderedDict(atoms)
+    correct_answer['atoms'] = OrderedDict(sorted(atoms.items()))
     return correct_answer
 
 
-def vsepr_grade(user_input, correct_answer):
-    print user_input, type(user_input)
-    print correct_answer, type(correct_answer)
+def vsepr_grade(user_input, correct_answer, ignore_p_order=False, ignore_a_order=False, ignore_e_order=False):
+    """ Flags ignore_(a,p,e)_order are for checking order in axial, perepherial or equatorial positions
+    """
+    # print user_input, type(user_input)
+    # print correct_answer, type(correct_answer)
     if user_input['geometry'] != correct_answer['geometry']:
         return False
-    if user_input['atoms'].values() != correct_answer['atoms'].values():
-        return False
-    return True
 
+    # not order-aware comparisons
+    for ignore in [(ignore_p_order, 'p'), (ignore_e_order, 'e'), (ignore_a_order, 'a')]:
+        if ignore[0]:
+            # collecting atoms:
+            a_user = [v for k, v in user_input['atoms'].items() if k.startswith(ignore[1])]
+            a_correct = [v for k, v in correct_answer['atoms'].items() if k.startswith(ignore[1])]
+            # print ignore[0], ignore[1], a_user, a_correct
+            if len(a_user) != len(a_correct):
+                return False
+            if sorted(a_user) != sorted(a_correct):
+                return False
+
+    # order-aware comparisons
+    for ignore in [(ignore_p_order, 'p'), (ignore_e_order, 'e'), (ignore_a_order, 'a')]:
+        if not ignore[0]:
+            # collecting atoms:
+            a_user = [v for k, v in user_input['atoms'].items() if k.startswith(ignore[1])]
+            a_correct = [v for k, v in correct_answer['atoms'].items() if k.startswith(ignore[1])]
+            # print '2nd', ignore[0], ignore[1], a_user, a_correct
+            if len(a_user) != len(a_correct):
+                return False
+            if len(a_correct) == 0:
+                continue
+            if a_user != a_correct:
+                return False
+
+    return True