new idea for duplicate edges

.gitignore

@@ -105,3 +105,6 @@ venv.bak/
 
 # data files
 referencePathways/reactome/*.gOut
+
+# output files
+*.sif

graphs/graph5/edges.txt

@@ -1,9 +1,12 @@
-A	B	0.98
-B	C	0.77
-A	D	0.12
-C	D	0.89
-C	E	0.59
-C	F	0.50
-F	G	0.76
-G	H	0.92
-G	I	0.66
+A	B	0.98	U
+B	C	0.77	U
+A	D	0.12	U
+A	D	0.12	D
+C	D	0.89	U
+C	E	0.59	U
+A	D	0.12	D
+C	F	0.50	U
+F	G	0.76	U
+G	H	0.92	U
+G	I	0.66	U
+B	C	0.77	U

minCostFlow.py

@@ -47,17 +47,19 @@ def construct_digraph(edges_file, cap):
             w = int((1-(float(tokens[2])))*100)
             d = tokens[3]
 
-            if d == "U":
+            # TODO: is it better to overwrite the edges or just to throw an error
+            if (node1, node2) in edges_dict:
+                raise KeyError(f"Failed to add the edge ({node1}, {node2}) with weight '{tokens[2]}' and directionality '{d}'. This edge conflicts with an existing '{edges_dict[(node1, node2)]}' edge in the graph.")
+            elif d == "U":
                 edges_dict[(node1, node2)] = "U"
                 edges_dict[(node2, node1)] = "U"
                 G.add_arc_with_capacity_and_unit_cost(idDict[node1],idDict[node2], default_capacity, int(w))
                 G.add_arc_with_capacity_and_unit_cost(idDict[node2],idDict[node1], default_capacity, int(w))
-
             elif d == "D":
                 edges_dict[(node1, node2)] = "D"
                 G.add_arc_with_capacity_and_unit_cost(idDict[node1],idDict[node2], default_capacity, int(w))
             else: 
-                raise ValueError (f"d = {d}")
+                raise ValueError (f"Cannot add egdge: d = {d}")
 
     idDict["maxID"] = curID
     return G,idDict