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Re: [sumo-user] Miscellaneous Queries

1) the simulation always runs as fast as it can and manages anywhere from 50k to 300k vehicle updates per second. This means a simulation of 600s (10min) may take anywhere from <1 s to hours depending on the number of vehicles being simulated

2) yes

3) there is (almost) no way to create congestion with a single flow. You need additional simulation elements for this. i.e. any of the following
   - a traffic light 
   - an intersection / on ramp and a second flow
   - a downstream section with lower speed
   - a variable speed sign that reduces speed
if the flow is running in a circle for a long time you can get spontaneous congestion by setting sigma > 0.7

3b) the default insertion lane is the right lane. If the flow is dense enough or the distribution of desired speeds is wide enough, vehicles will use the second lane for overtaking
To achieve use of both lanes on insertion use departLane="random" or "free" or "best"

4) arrivalLane must be defined in the <flow> or <vehicle> instead of the <vType>

5) if you use, set option --yfactor 3.6 (assuming speed is on the y-axis)

6) it means colors will be grouped according to edge id (you can safely ignore the warning)

7) 6 minutes and 40 seconds

8) there was an interval with density 10 and speed 44km/h however, you should plot density/speed with option --scatterplot since the density values are not sequential in any way thus the lines suggest intermediate points which do not exist

9) things to measure / compare between scenarios:
   - average timeLoss on road
   - minimum, maximum, average travel time on road  
   - maximum capacity on road (max vehs/hour observed)

Am Do., 17. Feb. 2022 um 22:52 Uhr schrieb Sumbal Malik <maliksumbal01@xxxxxxxxx>:
I would be thankful if you could answer the following queries:

1. How to measure the simulation default time? If the simulation runs for 600 time steps then is it equal to the actual 10 minutes?  If so then why does the simulation of (4404) end in just a few minutes?

2. <flow id="f" type="type1" probability="0.3" from="E1" to="E1" begin="0" end="1000" /> Does it mean that after every second there is 0.3 probability that a vehicle will depart and this flow will end after 1000 seconds?

3. How can to create traffic congestion using flow.

3. I created one edge with two lanes and generated traffic using sumo repeated flow but why are the vehicles traveling only on the right lane?

4. For one flow I defined this setting "<vType id="type1" vClass="truck" maxSpeed="30" color="red" arrivalLane="E1"/>" but in the trip output file I noticed that the vehicles are not following the set arrivalLane and mingap. I want the vehicles to arrive at Edge 1 lane 1 not one edge 1 lane 0

5. If the sumo measures the speed in meters per second then how can we convert it into kilometers per hour while plotting a graph?

6. Plotting a graph, " edge_data.xml -i id -x density -y speed -s --yfactor 3.6 -ylabel vehs/hour"  gives this the below warning. What does it mean?

Warning: found idattr 'id' in element 'interval' (level 2) and element 'edge' (level 3). Using 'edge'.

7. <edgeData id="dump_15" freq="400" file="edge_data.xml" excludeEmpty="true"/> here freq=400 means that the edges is collected after each six minutes?

8. In the attached graph speed versus density (> edge_data.xml -i id -x density -y speed -s --yfactor 3.6) what does density represent? Does it mean that at a certain interval if the density is 10 then the average speed of the vehicles is 44 km/h.

9. Please guide me on how can we calculate traffic efficiency? For example, if I say on a 2 km of road 1000 vehicles pass in a day due to congestion or delay but with a new approach, 1500 vehicles can pass in a day? How can we measure this kind of KPI.

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