Added abstracts to json, negative tests and bug fixes

verarbeitung/construct_new_graph/add_citations_rec.py

@@ -164,12 +164,16 @@ def process_citations_rec(citations_pub_obj_list, search_depth, search_depth_max
     '''
 
     # adds next level to nodes/edges
+
+    new_citation_pub_obj_save_list = []
     for pub in citations_pub_obj_list:
-        new_citation_pub_obj_list = create_graph_structure_citations(pub, search_depth, search_depth_max, cit_type, test_var)   
+        new_citation_pub_obj_list = create_graph_structure_citations(pub, search_depth, search_depth_max, cit_type, test_var)
+        if len(new_citation_pub_obj_list) > 0:
+            new_citation_pub_obj_save_list += new_citation_pub_obj_list
 
         # If the maximum depth has not yet been reached, calls function recursivly with increased depth 
-        if (search_depth < search_depth_max):
-            process_citations_rec(new_citation_pub_obj_list, search_depth+1, search_depth_max, cit_type, test_var)
+    if (search_depth < search_depth_max):
+        process_citations_rec(new_citation_pub_obj_save_list, search_depth+1, search_depth_max, cit_type, test_var)
 
 
 def add_citations(input_nodes, input_edges, citations_pub_obj_list, search_depth, search_depth_max, cit_type, test_var):