fix bugs in load_columns() and total_travel_time

- node path and link path shall be reversed in the loading process;
- check if a loaded column is existing following the same logic in
  colgen.py;
- fix bug in computing the total system travel time in
  _update_column_gradient_cost_and_flow(), where total_travel_time
  shall be updated before shifting flow.

Author: jdlph

path4gmns/colgen.py

@@ -113,8 +113,8 @@ def _update_column_gradient_cost_and_flow(column_pool, links, agent_types, iter_
 
         if least_gradient_cost_path_id != -1:
             col = cv.get_column(least_gradient_cost_path_id)
-            col.increase_volume(total_switched_out_path_vol)
             total_travel_time += col.get_sys_travel_time()
+            col.increase_volume(total_switched_out_path_vol)
 
     rel_gap = total_gap / max(total_travel_time, SMALL_DIVISOR)
 

path4gmns/utils.py

@@ -1052,63 +1052,56 @@ def load_columns(ui, input_dir='.'):
                 continue
 
             cv = A.get_column_vec(at, dp, oz_id, dz_id)
+            path_id = cv.get_column_num()
+            col = Column(path_id)
 
-            node_path = None
             try:
-                # "if x" check is only needed for columns generated from DTALite,
+                col.nodes = [A.get_node_no(int(x)) for x in reversed(node_seq.split(';')) if x]
+            except KeyError:
+                raise Exception(
+                    'Invalid node found on column!!'
+                    'Did you use agent.csv from a different network?'
+                )
+
+            try:
+                # if x is only needed for columns generated from DTALite,
                 # which have the trailing ';' and leads to '' after split
-                node_path = [int(x) for x in node_seq.split(';') if x]
+                col.links = [
+                    A.get_link_seq_no(x) for x in reversed(link_seq.split(';')) if x
+                ]
+            except KeyError:
+                raise Exception(
+                    'INVALID link found on column!!'
+                    'Did you use agent.csv from a different network?'
+                )
             except ValueError:
                 raise Exception(
-                    f'INVALID NODE PATH found for agent id: {agent_id}'
+                    f'INVALID LINK PATH found for agent id: {agent_id}'
                 )
 
+            # the following four are non-critical info
+            col.set_volume(vol)
+            col.set_toll(toll)
+            col.set_travel_time(tt)
+            col.set_geometry(geo)
+
             # deprecate node_sum and adopt the same implementation in colgen.py
             existing = False
-            for col in cv.get_columns():
-                if col.get_nodes() == node_path:
-                    col.increase_volume(vol)
-                    existing = True
-                    break
 
-            if not existing:
-                path_id = cv.get_column_num()
-                col = Column(path_id)
+            if dist == 0:
+                sum(A.get_link(x).get_length() for x in col.links)
 
-                try:
-                    col.nodes = [A.get_node_no(x) for x in node_path]
-                except KeyError:
-                    raise Exception(
-                        'Invalid node found on column!!'
-                        'Did you use agent.csv from a different network?'
-                    )
-
-                try:
-                    # if x is only needed for columns generated from DTALite,
-                    # which have the trailing ';' and leads to '' after split
-                    col.links = [
-                        A.get_link_seq_no(x) for x in link_seq.split(';') if x
-                    ]
-                except KeyError:
-                    raise Exception(
-                        'INVALID link found on column!!'
-                        'Did you use agent.csv from a different network?'
-                    )
-                except ValueError:
-                    raise Exception(
-                        f'INVALID LINK PATH found for agent id: {agent_id}'
-                    )
+            for col_ in cv.get_columns():
+                if col_.get_distance() != dist:
+                    continue
 
-                # the following four are non-critical info
-                col.set_volume(vol)
-                col.set_toll(toll)
-                col.set_travel_time(tt)
-                col.set_geometry(geo)
+                if col_.get_links() == col.links:
+                    col_.increase_volume(vol)
+                    existing = True
+                    break
 
-                if dist == 0:
-                    sum(A.get_link(x).get_length() for x in col.links)
+            if not existing:
                 col.set_distance(dist)
-
                 cv.add_new_column(col)
 
         update_links_using_columns(ui)

tests/demo.py

@@ -225,6 +225,8 @@ def test_simulation():
     column_gen_num = 10
     column_update_num = 10
     pg.perform_column_generation(column_gen_num, column_update_num, network)
+
+    # pg.load_columns(network)
     pg.perform_simple_simulation(network, 'uniform')
     print('complete simple simulation.\n')
 
@@ -279,4 +281,4 @@ def demo_mode(mode):
 
 if __name__=="__main__":
 
-    demo_mode(3)
+    demo_mode(10)