I am looking for a plugin for QGIS that can compare 2 layers and tell me which point features are not common to both and which features are separated by a distance of say plus 1 foot.

I am working on a project that we are collecting data on utility poles. We have to collect 100,000 poles and want to compare the position to the company’s data base of positions for the 100,000 poles. I am thinking in the simplest form I will have, what I call my field layer of collected poles w/XY values and the utility supplied layer consisting of information, including XY values.

How do I compare the layers and identify which poles are 1) not common to both and 2) Not within say a foot of each other?

I have 3 situations where I need this;

  1. A pole is not collected in the field because it no longer exists but the utility still has it in the data base
  2. A pole is collected but is more than a foot away from where it is supposed to be. We will need to re visit and determine if this a data collection error
  3. New poles that the company does not provide data for.

I will be using a gps equipped with a laser and camera and my requirement is to take a picture of the id tag but the laser allows us to do this from a distance. My problem is identifying when an operator collects data but not the utility pole but, say a house in the background. This will result in the XY values being > than a foot different. A foot is not my hard target just an example number.

  • Welcome to gis.stackexchange! Please note that a good question on this site is expected to show some degree of research on your part, i.e. what you have tried and - if applicable - code so far. For more info, you can check our faq. – underdark Jan 14 '18 at 0:20
  • What kind of GPS are you using? This is important as it will determine the level of accuracy each point will have. Some GPS will be accurate at the metre scale, so if you are looking at if a point is 1 foot away, this could be due to GPS uncertainty. You would need to look at differential GPS and to be getting sub 10cm accuracy for this project I imagine. – Liam G Jan 14 '18 at 2:47
  • I am using a sub meter gps so I get your point. The 1' was just a value I used . Since I am looking for a blunder that should be 1.5 meters. So I need to identify point that have an XY diff of +1.5 meters. – Andrew Hunter Jan 14 '18 at 23:20

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