Python调用VISSIM COM接口GetQueued方法报错的技术问询

Let's break down why you're hitting that com_error and how to fix it:

The Root Cause #

Your code calls cars.GetQueued() where cars is a Vehicles collection object returned by link1.GetVehicles(). The problem is straightforward: VISSIM's COM interface does not implement a GetQueued() method for the Vehicles collection. That's exactly what the error message "Not implemented method called." is telling you.

Correct Approaches to Get Queued Vehicle Data #

There are two reliable ways to retrieve queued vehicle information for a link via VISSIM's COM interface:

1. Get Queue Length & Count Directly (Simplest)

If you only need the number of queued vehicles or the physical queue length, use the GetQueueLength() method directly on the Link object. This returns a tuple with two values: queue length in meters, and the count of queued vehicles.

import win32com.client as com
vissim_com = com.Dispatch("Vissim.Vissim")
Sim = vissim_com.Simulation
vissim_com.LoadNet(r'D:\Tracer\labprogramme\vissim\test.inp')
vnet = vissim_com.net
links = vnet.Links
link1 = links.GetLinkByNumber(1)  # Fixed typo: GetLinkByNUmber → GetLinkByNumber
Sim.Period = 3600

for i in range(3600):
    Sim.RunSingleStep()
    # Extract queue metrics directly from the link
    queue_length, queued_vehicle_count = link1.GetQueueLength()
    print(f"Step {i}: Queued vehicles: {queued_vehicle_count}, Queue length: {queue_length}m")

2. Filter Vehicles to Get Queued Objects

If you need access to the actual queued Vehicle objects (e.g., to check individual vehicle properties), iterate over all vehicles on the link and use their IsQueued property to filter:

import win32com.client as com
vissim_com = com.Dispatch("Vissim.Vissim")
Sim = vissim_com.Simulation
vissim_com.LoadNet(r'D:\Tracer\labprogramme\vissim\test.inp')
vnet = vissim_com.net
links = vnet.Links
link1 = links.GetLinkByNumber(1)
Sim.Period = 3600

for i in range(3600):
    Sim.RunSingleStep()
    cars = link1.GetVehicles()
    queued_cars = []
    for car in cars:
        if car.IsQueued:  # Check if the vehicle is in queue state
            queued_cars.append(car)
    print(f"Step {i}: Number of queued vehicles: {len(queued_cars)}")

Quick Additional Notes #

• I fixed a small typo in your original code (GetLinkByNUmber → GetLinkByNumber)—this could have caused an extra error if left unaddressed!
• If you're using an older VISSIM version, double-check the VISSIMCOM.HLP file mentioned in your error for version-specific method names (some older builds use QueueLength instead of GetQueueLength).

内容的提问来源于stack exchange，提问作者tracer