fix bug introduced in _get_interval_id() by PR#12

- the interval i calculation should follow
  (MIN_TIME_BUDGET + (i-1)*BUDGET_TIME_INTVL, MIN_TIME_BUDGET + i*BUDGET_TIME_INTVL],
  where, i is integer and i >= 1.

Author: jdlph

engine/path_engine.cpp

@@ -17,6 +17,7 @@
 using std::wcsstr;
 using std::wcscmp;
 
+// keep it as legacy support for other packages using this old engine
 void shortest_path(int o_node_no,
                    int node_size,
                    const int* from_node_no_arr,

path4gmns/accessibility.py

@@ -17,15 +17,15 @@ def _get_interval_id(t):
     [0, MIN_TIME_BUDGET],
 
     (MIN_TIME_BUDGET + (i-1)*BUDGET_TIME_INTVL, MIN_TIME_BUDGET + i*BUDGET_TIME_INTVL]
-        where, i is integer and i>=1
+        where, i is integer and i >= 1
     """
     if t < MIN_TIME_BUDGET:
         return 0
 
     if ((t-MIN_TIME_BUDGET) % BUDGET_TIME_INTVL) == 0:
-        return int((t-MIN_TIME_BUDGET) % BUDGET_TIME_INTVL)
+        return int((t-MIN_TIME_BUDGET) / BUDGET_TIME_INTVL)
 
-    return int((t-MIN_TIME_BUDGET) % BUDGET_TIME_INTVL) + 1
+    return int((t-MIN_TIME_BUDGET) / BUDGET_TIME_INTVL) + 1
 
 
 def _update_min_travel_time(an, at, min_travel_times, time_dependent, demand_period_id):
@@ -242,6 +242,7 @@ def evaluate_accessibility(ui,
 
     interval_num = _get_interval_id(min(max_min, MAX_TIME_BUDGET)) + 1
 
+    # multithreading to reduce output time
     t = threading.Thread(
         target=_output_accessibility,
         args=(min_travel_times, zones, mode, output_dir))
@@ -251,4 +252,4 @@ def evaluate_accessibility(ui,
         target=_output_accessibility_aggregated,
         args=(min_travel_times, interval_num, zones, ats, output_dir)
     )
-    t.start()
+    t.start()