Skip to main content
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [List Home]
Re: [sumo-dev] Lead vehicle type in Wiedemann car-following model
Hello,
The value of pred may be a nullpointer in some calling contects among which is lane-changing (the followspeed function is not only used when car-following but also when determining appropriate gaps for lane-changing). Therefore, instead of
std::cout << " pred ID=" << pred->getID();
use
if (pred != 0) {
  std::cout << " pred ID=" << pred->getID();
}


2018-04-06 17:56 GMT+02:00 Umair Durrani <durraniu@xxxxxxxxxxx>:
Thank you. I won't bother you with common C++ programming issues in future. But I think I have encountered an error that is related to multiple files where pred has been introduced.

As you suggested, I printed the pred->getID() in MSCFModel_Wiedemann::followSpeed() function before the return statement:  

MSCFModel_Wiedemann::followSpeed(const MSVehicle* const veh, double /* speed */, double gap2pred, double predSpeed, double /*predMaxDecel*/, const MSVehicle* const pred) const {
    std::cout << " pred ID=" << pred->getID();
return _v(veh, predSpeed, gap2pred);
}

With this change (and build) I ran a simulation where the ego vehicle starts from a ramp and enters a highway. Initially there was no pred vehicle so nothing was printed. When the ego vehicle approached the highway, the pred vehicle on the highway was pred1 until time step 42 (see attached image). However, at this time another vehicle (pred2) was passing the ego vehicle. This means that in time step 43 (or the end of 42), the pred2 becomes the pred vehicle. But the simulation throws an error at the end of time step 42. 

I suspect this is because of the change in pred->getID(). But in the simulation it is expected that pred vehicle could change at any time. 

Can you please help me fix this? 

best regards,
Umair Durrani 
Ph.D. Candidate
Civil and Environmental Engineering

On Fri, Apr 6, 2018 at 1:59 AM, Jakob Erdmann <namdre.sumo@xxxxxxxxxxxxxx> wrote:
The function MSCFModel_Wiedemann::_v does not have access to the lead vehicle.
You must either add another parameter to that function and modify the call to _v in MSCFModel_Wiedemann::followSpeed or you just do your printing in
MSCFModel_Wiedemann::followSpeed before the call to _v (i.e. pred->getID()).
I advise seeking programming guidance on your campus as you will run into lots of questions like these and general programming help is beyond the scope of this mailing list.

regards,
Jakob

2018-04-06 1:12 GMT+02:00 Umair Durrani <durraniu@xxxxxxxxxxx>:
Thanks for your help.

Coming back to the lead vehicle, how do I use the pred object? To clarify, I mean that for the veh object I get the information from MSVehicle.h and MSVehicleType.h files. For example within the _v() function, I can do:

std::cout << veh->getID();

But where do I get the ID and other attributes of pred?  Could you please give me an example of printing the lead vehicle ID and type/class in the _v() function?

I am really thankful for your patience and help.



best regards,
Umair Durrani 
Ph.D. Candidate
Civil and Environmental Engineering

On Thu, Apr 5, 2018 at 2:39 PM, Jakob Erdmann <namdre.sumo@xxxxxxxxxxxxxx> wrote:
You need a working installation of python and then the version.h file is automatically generated during the build process.


2018-04-05 20:32 GMT+02:00 Umair Durrani <durraniu@xxxxxxxxxxx>:
Thanks. I have downloaded it from github.

However, when I build it I get an error:  Cannot open include file: 'version.h': No such file or directory  

So, I opened an github issue:  Error: Cannot open include file: 'version.h': No such file or directory #3967 on sumo master.  

best regards,
Umair Durrani 
Ph.D. Candidate
Civil and Environmental Engineering

On Thu, Apr 5, 2018 at 2:27 PM, Jakob Erdmann <namdre.sumo@xxxxxxxxxxxxxx> wrote:
the files at http://sumo.dlr.de/wiki/Downloads#SUMO_-_Latest_Development_Version are only updated during the night. If you download tomorrow you should be able to get them there.
Alternatively, download them directly from github: https://github.com/DLR-TS/sumo/archive/master.zip

regards,
Jakob

2018-04-05 17:16 GMT+02:00 Umair Durrani <durraniu@xxxxxxxxxxx>:
Hi Jakob,

Thanks for your reply. I see that you made changes few hours ago.  I'm very new to git/github and developement so please bear with me. 

Based on the commit ID you provided, I found that the changes are shown on this URL: https://github.com/DLR-TS/sumo/commit/8f43c4a6874690c0a41443b1efbead0e4384f921  

So, I thought when I download the development version from this link: (http://sumo.dlr.de/wiki/Downloads#SUMO_-_Latest_Development_Version)  I'd get the new files

However, I don't see any changes in the files. Where can I download the latest development version that includes those followSpeed() changes that you recently made?



best regards,
Umair Durrani 
Ph.D. Candidate
Civil and Environmental Engineering

On Thu, Apr 5, 2018 at 3:31 AM, Jakob Erdmann <namdre.sumo@xxxxxxxxxxxxxx> wrote:
Hello,
in the very latest development version (8f43c4a6874690c0a41443b1efbead0e4384f921) the followSpeed() API includes a parameter for the lead vehicle. Note, that in some calling contexts, this value may be a nullpointer
regards,
Jakob

2018-04-03 20:23 GMT+02:00 Umair Durrani <durraniu@xxxxxxxxxxx>:
Hi,

I am looking into the Wiedemann model and related
​.​
cpp and .h files in the development version of SUMO.   

Is there a way to print or do something with the LEAD vehicle type in the MSCFModel_Wiedemann.cpp?. I found 'gap2pred' and 'predspeed' but nothing like 'predType' or 'predClass'.

Ideally, I want to change the behavior of following vehicle if the lead vehicle class is a truck. 

best regards,
Umair Durrani 
Ph.D. Candidate
Civil and Environmental Engineering


_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev



_______________________________________________
sumo-dev mailing list
sumo-dev@xxxxxxxxxxx
To change your delivery options, retrieve your password, or unsubscribe from this list, visit
https://dev.eclipse.org/mailman/listinfo/sumo-dev


Back to the top