1

At ArcGIS Desktop 10.5, I have a polygon file geodatabase feature class. Many of its polygons are spatially coincident; that is, if I click on a single polygon in Arcmap to select it, the resulting selection will have multiple records, all sharing the same exact polygon outline. Here's a screenshot example where one polygon is selected, resulting in 74 selected records. In my mind, they represent 74 polygons stacked upon each other.

enter image description here

The attribute table contains a long integer field, noise_value. I need to sum this field for each input polygon, which, as I mentioned above, may be comprised of multiple spatially coincident polygons, and output the result to a new, flattened, polygon feature class containing the summed value.

In my example, the 74 overlapping polygons would be reduced to a single output polygon with a summed noise_value. Of course, this summation would have to be repeated for all input polygons.

I've tried these approaches, and all have failed:

1. Flatten the input feature class while applying the field map merge rule "SUM" for the noise_value attribute.

I tried this approach with the Feature Class to Feature Class tool as well as the Merge tool. In each case the output was identical to the input; no flattening or summing occurred.

2. Create a flattened output feature class and then spatially join it to the original feature class, summing by noise_value with field map merge rule SUM.

I tried this approach with the Feature to Polygon tool, and also with the Union tool to create the flattened output feature class. Both cases failed, with a "Topoengine error". Research indicates that this type of error can be traced to inadequate hardware resources, but I'm using a computer with an i7 processor, 16GB ram and a 1 TB SSD.

3. Use the Dissolve tool (@BERA's suggestion) with noise_value as the statistics field and Statistics Type = SUM.

Since what I want to do is flatten (dissolve) the geometry, I left the Dissolve Field blank. The result did not work for me because it created a single output polygon with one overall summed noise_value.

I've run out of ideas, and am looking for advice.

PolyGeo
  • 65,136
  • 29
  • 109
  • 338
Stu Smith
  • 8,252
  • 8
  • 35
  • 84
  • You should take a look at the dissolve tool – BERA Jun 30 '17 at 18:25
  • If you want more than one polygon after a dissolve, I'm fairly certain you need to select something in the Dissolve field. – Emily Jun 30 '17 at 20:02
  • Add geometry attributes, centroid. Concatenate them into single text field. Apply dissolve on this field. Consider rounding coordinates using something like https://gis.stackexchange.com/questions/125090/assign-point-ids-to-respective-start-and-end-attributes-of-a-polyline/125091#125091 – FelixIP Jul 01 '17 at 00:44
  • @FelixIP, perfect! Calculating the centroid is a great way to do a geometry dissolve. In my dissolve on the centroid, I used noise_value as the statistics field with statistics_type = SUM. The result was just what I was looking for. If you want to reform your comment as an answer, I'd be happy to give you credit. – Stu Smith Jul 01 '17 at 15:44

0 Answers0