Take the 2-minute tour ×
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It's 100% free, no registration required.

I'm checking polylines to make sure power pylons were correctly extracted from imagery. Is there a way to find all of the gaps or missed pylons in the database? Currently, I'm manually making a point file from the vertices on the line and checking inconsistencies at a high level. I thought of making a buffer and looking the areas that didn't overlap, but the power pylons are gapped at different distances so it would take forever to run several different buffers for every line in the database. Any other ideas for a more efficient process?

share|improve this question
    
It sounds like you are looking for dangling nodes. What version and license level of ArcGIS for Desktop are you using? –  PolyGeo May 23 '13 at 5:13
    
ArcInfo 10.1. Looking for nodes and spacing of vertexes. Is there some sort of script to point out irregular spacing on lines? –  joebob Jul 2 '13 at 16:52
1  
Maybe you could add a photo to better describe the "missed" gaps you are looking in your data? That would help identify a solution to your issue. –  RyanDalton Jul 2 '13 at 19:12
    
I mean like missed pylons going in a line. Right now I'm just running verticies to points then creating buffers to manually verify at a high level. I was more so asking if there is a way to run a script that can tell if a pylon was missed in a line based of of a gap. Lets say the distance is ~30m apart and one was missed so there would ~60m of gap between them. –  joebob Jul 2 '13 at 20:39
    
Not sure how your data actually looks but have to looked at topology rules? Creative use of them might be able to be help. Otherwise set a script to add a column for distance between points? –  eseglem Aug 2 '13 at 11:43
add comment

1 Answer 1

I'm assuming that that you are using Feature Vertices To Points to convert the vertices on your polylines to points. This will mean that the ORIG_FID will enable you to tell which points come from which line.

You should then be able to use Point Distance with a suitable search radius to create a table of each point to its N nearest points.

By using Join Field twice, once for INPUT_FID and then for NEAR_FID, and taking care to "rename" the ORIG_FID from the output of Feature Vertices to Points each time before you join, so that you can distinguish the line each came from, you should be able to identify all points (pylons) from the same line with a distance of more than 60m between them.

share|improve this answer
    
Yes, I've been using Feature Verticies to Points. How do you get the Point Distance to work if I only have one feature class to get the distances from? –  joebob Jul 3 '13 at 20:44
1  
"Both Input Features and Near Features can be the same dataset. In that case, when the input and near features are the same record, that result will be skipped so as not to report that each feature is 0 units from itself." –  PolyGeo Jul 3 '13 at 20:52
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

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