questions about test result

[BIT-TYJ]

Hello, I have some questions about the testing datasets.
First, for dataset in /data/example_2robots, why are the serial numbers of vertexs in both 0.g2o and 1.g2o not continuous? And how does the optimized results sort the vertexs of two robots?
Second, I have tried to make a two robot dataset as follows:
for 0.g2o:
VERTEX_SE3:QUAT 1 0 0 0 0 0 0 1
VERTEX_SE3:QUAT 2 0 0 0 0 0 0 1
VERTEX_SE3:QUAT 3 0 0 0 0 0 0 1
VERTEX_SE3:QUAT 4 0 0 0 0 0 0 1
EDGE_SE3:QUAT 1 2 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 2 3 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 3 4 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 1 3 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 3 6 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 3 5 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
for 1.g2o:
VERTEX_SE3:QUAT 5 0 0 0 -0.7071067811865475 0.0 0.0 0.7071067811865475
VERTEX_SE3:QUAT 6 0 0 0 -0.7071067811865475 0.0 0.0 0.7071067811865475
VERTEX_SE3:QUAT 7 0 0 0 -0.7071067811865475 0.0 0.0 0.7071067811865475
VERTEX_SE3:QUAT 8 0 0 0 -0.7071067811865475 0.0 0.0 0.7071067811865475
EDGE_SE3:QUAT 5 6 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 6 7 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 7 8 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 3 6 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1
EDGE_SE3:QUAT 3 5 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1

The output from terminal is
"Graph is disconnected:
Copying initial to optimized"

Looking forward to your reply! Thank you very much!

[itzsid]

Hi @BIT-TYJ,

All the vertices corresponding to the first robot will be prefixed using 'a' using gtsam.Symbol like gtsam.Symbol('a', 1), gtsam.Symbol('a',2) etc. Similarly the second robot will be prefixed using 'b' like gtsam.Symbol('b', 1), gtsam.Symbol('b',2). Code extracts the robot prefix to know which robot the vertex belongs to. You should use the same format and see if it works.

[BIT-TYJ]

Thank you. I will try it.

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---Original--- From: "Siddharth ***@***.***> Date: Tue, Apr 12, 2022 09:40 AM To: ***@***.***>; Cc: ***@***.******@***.***>; Subject: Re: [CogRob/distributed-mapper] questions about test result (Issue #8) Hi @BIT-TYJ, All the vertices corresponding to the first robot will be prefixed using 'a' using gtsam.Symbol like gtsam.Symbol('a', 1), gtsam.Symbol('a',2) etc. Similarly the second robot will be prefixed using 'b' like gtsam.Symbol('b', 1), gtsam.Symbol('b',2). Code extracts the robot prefix to know which robot the vertex belongs to. You should use the same format and see if it works. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you were mentioned.Message ID: ***@***.***>

[BIT-TYJ]

dear author in fact, I don't know the meaning of long number of a vertex like 6989586621679009729, if I want to design .g2o files myself, I don't know which number of a vertex is valid for code to identify. 

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---Original--- From: "Siddharth ***@***.***> Date: Tue, Apr 12, 2022 09:40 AM To: ***@***.***>; Cc: ***@***.******@***.***>; Subject: Re: [CogRob/distributed-mapper] questions about test result (Issue #8) Hi @BIT-TYJ, All the vertices corresponding to the first robot will be prefixed using 'a' using gtsam.Symbol like gtsam.Symbol('a', 1), gtsam.Symbol('a',2) etc. Similarly the second robot will be prefixed using 'b' like gtsam.Symbol('b', 1), gtsam.Symbol('b',2). Code extracts the robot prefix to know which robot the vertex belongs to. You should use the same format and see if it works. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you were mentioned.Message ID: ***@***.***>

[itzsid]

@BIT-TYJ, you will have to create a GTSAM graph and write to a g2o file. You can checkout: https://gtsam.org/tutorials/intro.html on how to create GTSAM graph. Look at this example on how to write to g2o file: https://github.com/devbharat/gtsam/blob/master/examples/Pose2SLAMExample_g2o.cpp