topic Re: Add Unique ID from one polygon layer to another based on spatial relationship in Spatial Data Science Questions

Add Unique ID from one polygon layer to another based on spatial relationship

JensJensen — Thu, 18 May 2017 05:51:46 GMT

Hello

I'm have two polygon layers, one have been dissolved, the other is the original data with a lot of smaller polygons in it. The polygon layers overlap each other.

Each of the dissolved polygons have an unique id, that I would like to add to all the smaller polygons, so I can see where the smaller polygons belong.

I'm thinking some kind of join or similar based on the spatial relationship (overlap), but I can't get it too work. Tried adding a concept illustration:

Input:		Wanted output
Dissolved polygon ID	Size	Small polygon size	Small polygon ID
4479	10	1	4479
		1	4479
		1	4479
		1	4479
		1	4479
		1	4479
		1	4479
		1	4479
		1	4479
		1	4479

Re: Add Unique ID from one polygon layer to another based on spatial relationship

FC_Basson — Thu, 18 May 2017 06:05:22 GMT

You should be able to accomplish this with a Spatial Join: Spatial Join—Help | ArcGIS for Desktop

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JayantaPoddar — Thu, 18 May 2017 06:17:32 GMT

Check the following steps

1. Convert the small polygons to points layer Feature To Point—Help | ArcGIS Desktop

2. Do a Spatial Join to migrate the data from the Dissolved Polygons to the Points.

3. Do a Spatial Join again to migrate the data from points to smaller polygons.

4. Delete the unwanted fields from the layer with smaller polygons. Delete Field—Help | ArcGIS Desktop

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JensJensen — Thu, 18 May 2017 06:55:17 GMT

Thank you, both of the suggestion works. Much appreciated.

Another question a bit different, can you convert a raster too vector, without it grouping raster cells, so that basically each raster cell becomes a polygon?

Input raster			Unwanted output vector			Wanted output in vector
No data	1	No data	No data	1	No data	No data	1	No data
3	1	8	3	1	8	3	1	8
2	2	4	2		4	2	2	4

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JensJensen — Thu, 18 May 2017 07:00:46 GMT

Had to do a few different version of this, but got it to work, thanks!

I've added an extra credits question to Jayantas comment, feel free to weigh in, if you know the answer

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JayantaPoddar — Thu, 18 May 2017 07:12:05 GMT

Check How To: Convert each pixel of a raster into a polygon

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JensJensen — Thu, 18 May 2017 07:15:00 GMT

That would work perfectly, just one little hiccup I only have an ArcGIS Standard license with Spatial Analyst.

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JayantaPoddar — Thu, 18 May 2017 07:40:24 GMT

Alright.

While creating Fishnet, keep Geometry Type as Polygon.

Then do a Spatial Join to migrate the values of points to the polygons.

*No need to do Feature to Polygon step

Re: Add Unique ID from one polygon layer to another based on spatial relationship

JensJensen — Thu, 18 May 2017 09:20:43 GMT

How did I miss that I could create polygons with the fishnet. Thank you very much, exactly what I needed!