1

Objective: Convert different single part features with same attribute in a field (say 'Country') to a single multipart feature while retaining original geometries.

I have been looking for an ArcMap alternative of collect geometries tool available in QGIS 3.0+ but strangely enough, couldn't find it.

Closest match probably is dissolve tool which is identical to 'Collect Geometries' tool in QGIS as far as features (with same country name) are disjoint. For overlapping or adjacent features, it doesn't retain the original shapes and dissolve the shapes as well. I have also tried union and different other tools but no success.

I am open to ArcPy solutions as well. I hope that this image will help to understand the concept.

this image

  • Dissolve has a "Create multipart features" checkbox in the UI; wouldn't this accomplish your goal? Either way, your lower-right "Required" box isn't clear. – Vince Dec 11 '19 at 19:55
  • 2
    Dissolve would merge the overlapping features into a single part of the multipart feature. Judging from the 'Required' illustration, I believe he wants to retain separate overlapping parts within a multipart feature (which seems an unusual requirement to us when we don't know the reasons why). – Son of a Beach Dec 11 '19 at 21:35
  • Thank you very much for the answers. Dissolve works perfect if the features are disjoint. However, for adjacent or overlapping features, original shapes aren't retained. @Vince, "Required" shows that original shapes are retained even when the features have been converted to a single feature. – Badar Munir Dec 12 '19 at 9:58
  • @Son of a Beach, Yes, I want to retain separate overlapping/adjacent parts within a multipart feature. The purpose is just to make features handling for surveyors, easy. – Badar Munir Dec 12 '19 at 10:04
  • 1
    It is not possible to construct topologically invalid geometries with Esri tools. Polygon rings are forbidden from overlapping or touching at more than a point. When you Union shapes, the overlap is always erased. Collections are not supported, either within the same topology class or across different classes. – Vince Dec 12 '19 at 11:55
0

Thank you Vince for your comments. If you had answered the question, I would have marked it as accepted answer.

So the answer is, the requirement I stated above leads to topologically invalid polygons and Esri environment doesn't allow it. I have produced my desired output shapefile in QGIS and tried to open it in ArcMap. It opens fine but the common/overlapping area is stripped while rendering. Following image may explain the concept better. Please note that the shapefile in image has just one multipart feature having FID=0.

Image

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.