Question

FME Desktop geometry matching

  • 3 December 2018
  • 5 replies
  • 5 views
G

Hi All,

I am doing the feature matching. wherein I have two sources [Line feature] and I am using a distance chopper to chop the line feature at a specific distance and then neighbor finder to find the nearest feature. but I am getting some falls positive in my final output. not sure what is going wrong.

In input layers, there is no common attribute which can be used at later stages.

Can someone suggest a solution to this?

 

Please Find the attached screenshot herewith. in this screenshot blue line is one source, the green line is another source used for matching. and red lines are output.

 

5 replies

redgeographics
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On a general note: please make sure to enter an appropriate title for your question, this helps us help you (try and see if you can edit it)

 

So regarding your question: I assume you want to find features that exist in the green set but not in the blue and because the geometries don't line up you need to use the NeighborFinder, am I right? And the false positives would be the little red bits you see in the center of the image?

What I'm guessing it happening is that they fall just outside of the maximum distance you specified in the NeighborFinder, increasing that should match them, but if you increase it too much you'll run the risk of causing more problems than you're fixing.

G

On a general note: please make sure to enter an appropriate title for your question, this helps us help you (try and see if you can edit it)

 

So regarding your question: I assume you want to find features that exist in the green set but not in the blue and because the geometries don't line up you need to use the NeighborFinder, am I right? And the false positives would be the little red bits you see in the center of the image?

What I'm guessing it happening is that they fall just outside of the maximum distance you specified in the NeighborFinder, increasing that should match them, but if you increase it too much you'll run the risk of causing more problems than you're fixing.

@redgeographics Thank you for the reply .. made some changes in my Question header :)You are right I want to remove those small part from my output. I am using the distance of 100 m in neighbor finder. The maximum part of a line having these part is getting matched and it misses only these small part from matching and send it through the unmatched candidate. these part are at a distance of 90 meters and I am using 100 meters as a distance in neighbourfinder.

redgeographics
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Userlevel 5
Badge +25

@redgeographics Thank you for the reply .. made some changes in my Question header :)You are right I want to remove those small part from my output. I am using the distance of 100 m in neighbor finder. The maximum part of a line having these part is getting matched and it misses only these small part from matching and send it through the unmatched candidate. these part are at a distance of 90 meters and I am using 100 meters as a distance in neighbourfinder.

Check the distance between the actual vertices, because that's what the Neighborfinder is basing its calculations on.

G

Check the distance between the actual vertices, because that's what the Neighborfinder is basing its calculations on.

@redgeographics checked the distance and it's around 89.564 m

redgeographics
Rank
Userlevel 5
Badge +25

@redgeographics checked the distance and it's around 89.564 m

Can you share your sample data with us?

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