I have recently aggregated 6 spatially identical MapInfo TABs in FME. The data has Lotplan and PPN attributes that are then used to group by in the aggregation:

enter image description here

The polygons and figures in the resultant output appear completely fine with all the Floor Area (float)attribute data being correct. Then these polygons are taken into MapInfo and split by another polygon layer with Floor Area figures split proportionally based on the new split area. The problem is that the resulting Floor Area data is divided by 6 (the number of input datasets) consistently across the dataset.

I have worked around this problem by multiplying the figures by 6.

closed as unclear what you're asking by Mapperz Sep 21 '16 at 15:25

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  • Please refer to Mark Ireland's Answer and edit your question to clarify what you are expecting as an outcome? – Mapperz Sep 21 '16 at 15:26

The question is, what do you want in MapInfo?

  • Do you want six features, each with a geometry and its own attributes?
  • Do you want one feature with one geometry, and all of the attributes?
  • Do you want six features, each with a geometry and all of the attributes?
  • Do you want one feature with six geometries and all of the attributes?

If so...

  • Do nothing. Just open the data directly in MapInfo
  • Use a FeatureMerger with one source as Reqestor the others are Suppliers
  • Do as the above line, but use a Cloner to create six copies
  • This is what you have now.

To me it's not clear what you want out of FME and in MapInfo, but I figure that you probably want the FeatureMerger instead of the Aggregator transformer.

  • Hi Mark, yes I am after one feature with one geometry and all the attributes. I will try the FeatureMerger option thanks! – Vass Sep 23 '16 at 0:00
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    Using the FeatureMerger (Merge Type "Attributes Only" and joining on Lotplan & PPN) in place of the 2nd Aggregator worked perfectly. Thank you very much Mark. I've got a better idea about how the Aggregator works now too. Cheers. – Vass Sep 23 '16 at 1:16

The reason you are getting 1/6 the floor area is because the output from FME has the geometry type as aggregate, with each row having 6 features. You have likely averaged or taken the first area for each row, so that is being divided by 6.

To get around this, add an AreaOnAreaOverlayer after the Aggregator. Set your group by attributes the same as the aggregator. This will output a file with geometry type set to polygon(area) and will have one feature per row.

I tested this using FME 2016.0 64 bit. Please test this solution with your data and post the results.

enter image description here

  • I really don't know what the AreaOnAreaOverlayer is meant to achieve here. All I can think of is that it deaggregates the features - in that case you could use a Deaggregator instead, but in that case why aggregate the data in the first place?! – Mark Ireland Sep 21 '16 at 14:54

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