[sumo-dev] Issue with `traci4matlab\+traci\sendExact.m`

[Tushar Choudhary <tusharc.cse@xxxxxxxxx>]

Hi,

I am a undergrad student and i am trying to use SUMO for a simulation script on matlab. This script invokes sumo.exe and sends some data to simulate an environment with mobile vehicles to study some networking algorithms for V2X communication.

While trying to invoke SUMO for the same i am hitting the following issue:

 

Dot indexing is not supported for variables of this type.
Error in traci.sendExact (line 19)
activeConnection.dos.writeInt(len);

The variable in question here is the "connection" variable in the following script `\SUMO\tools\contributed\traci4matlab\+traci\sendExact.m` .

function result = sendExact()

%sendExact An internal function to send a message to the SUMO server and

%parse the result.

% Copyright 2019 Universidad Nacional de Colombia,

% Politecnico Jaime Isaza Cadavid.

% Authors: Andres Acosta, Jairo Espinosa, Jorge Espinosa.

% $Id: sendExact.m 48 2018-12-26 15:35:20Z afacostag $

global message connections

import traci.constants

% warning('off','instrument:fread:unsuccessfulRead');

% Length of the command

len = 4 + length(message.string);

activeConnection = connections('');

% Write the message to the tcp socket

activeConnection.dos.writeInt(len);

activeConnection.dos.write(message.string);

% Read the result from the socket

result = traci.recvExact();

if isempty(result)

fclose(connections(''));

clear connections('')

throw(MException('traci:FatalTraciError','Connection closed by SUMO\n'))

end

% Parse the result

for i= 1:length(message.queue)

prefix = result.read(3);

if prefix(3)==0

strresult = 'OK';

elseif prefix(3)==1

strresult = 'Not Implemented';

else

strresult = 'Error';

end

err = result.readString();

if prefix(3) || ~isempty(err)

message.string = [];

message.queue = [];

traci.close();

throw(MException('traci:FatalTraciError','%s %s %s\n', num2str(prefix), strresult, err));

elseif prefix(2) ~= message.queue(i)

traci.close();

throw(MException('traci:FatalTraciError','Received answer 0x%.2X for command 0x%.2x.\n',...

prefix(2), message.queue(i)));

elseif strcmp(prefix(2),constants.CMD_STOP)

len = result.read(1) - 1;

result.read(len + 1);

end

end

% Clear the message contents

message.string = [];

message.queue = [];

In the above code the "connections" variable is defined as a global variable and later it is used as a function and the output is stored in the variable "activeConnections". This seemingly is faulty in nature.

It would be really helpful if someone could help me navigate through this issue.

Regards

--

Tushar Choudhary

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