Question

dissolver failure

  • 18 February 2015
  • 7 replies
  • 17 views

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Hi there,

 

Anyone has an idea what may be wrong? I suspect that I reached some limit with the dissolver function. In easy cases it just works OK. But when I do dissolving of a 2500 polygons into one, it just forgets to create the donuts inside.

 

This is my input:

 

 

This is what I expect:

 

 

 

and this is what I actually get:

 

 

 

Any help is highly appreciated. Thank you in anticipation,

 

Jaroslav

 

 

7 replies

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Update: the problem is not related to the number of polygons but to the bad guy which is the big donut-circle around.
Userlevel 3
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Hi Jaroslav,

 

 

I was not able to reproduce similar situation to yours anyhow. Unavoidable computational error sometimes may cause such an exceptional result, but the exact reason is unclear.

 

I would recommend you to contact Safe support and send the data and workspace which reproduce the situation.

 

 

Takashi
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Just for case, if anyone is interested:

 

I applied the tiler to the donut circle splitting it into about 10 pieces and dissolved it with other polygons this way and it worked.
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Conclusion: the dissolver does not work with the geometry type "FME donut". The detailed analysis showed I was trying to dissolve a lot of "FME polygons" with a "FME donut" which lead to incorrect results. Once I applied the DonutBridgeBuilder, it was converted to "FME polygon" and dissolved as it should.
Userlevel 3
Badge +17
This may also be the "ellipse vs. ellipse" issue. (https://drive.google.com/file/d/0B0ufVP2t0eApMVZkT1J2dkRoRDA/view?usp=sharing)
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Thanks Takashi. It might be some computational error, but I am OK with the workaround by now.
thank you Jaroslav,

 

using the DonutBridgeBuilder to convert the "FME donut" geometries also fixed my problem with the Dissolver!

 

 

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