topic Re: How can I auto-connect polygons in ArcGIS 10.3? in New to GIS Questions

How can I auto-connect polygons in ArcGIS 10.3?

SteveSkotnicki — Wed, 17 Jun 2015 20:11:49 GMT

I am new to ArcGis, and I am creating a large number of adjacent polygons for a geologic map that share edges. How can I connect one polygon to another such that the topology will contain no gaps, and will allow me NOT to have to redraw the shared edge(s)?

Re: How can I auto-connect polygons in ArcGIS 10.3?

DarrenWiens2 — Wed, 17 Jun 2015 20:16:44 GMT

Have you already started drawing? If not, I've found it easier to start with a large polygon covering your entire area, and cutting it into smaller contiguous pieces than to draw new polygons.

Aside from that, you may be interested in topology editing.

Re: How can I auto-connect polygons in ArcGIS 10.3?

IanMurray — Wed, 17 Jun 2015 20:22:48 GMT

Agreed Darren, that is a much easier procedure then trying to get a bunch of polygons to be coincident with each other. Sometimes its worth it even if you already started drawing since it saves so much time trying to line up vertices and edges.

Re: How can I auto-connect polygons in ArcGIS 10.3?

WesMiller — Wed, 17 Jun 2015 20:36:07 GMT

If you've already started drawing use the Auto-Complete polygon tool. it's at the bottom of your create features dialog Darren Wiens is correct drawing one large poly and cutting the smaller ones is easier.

Re: How can I auto-connect polygons in ArcGIS 10.3?

SteveSkotnicki — Wed, 17 Jun 2015 20:56:08 GMT

Thank you guys. I see the Auto Complete Polygon tool at the bottom of Complete Features.

If I create one large polygon (say, the outside boundary of the map) and then cut it up into smaller and smaller polygons, doesn't that necessitate beginning at the edge of the map and working inward? This technique seems a little primitive. It is really the most effective method?

Re: How can I auto-connect polygons in ArcGIS 10.3?

WesMiller — Wed, 17 Jun 2015 20:59:14 GMT

It makes it less likely you'll create gaps between the polygons.. When using the cut polygon tool i like to start on the outside of the polygon and finish on the outside of the polygon so you wont get the unable to complete operation message. I think it's faster to do it this way too.

Re: How can I auto-connect polygons in ArcGIS 10.3?

FilipKrál — Wed, 17 Jun 2015 21:00:21 GMT

Hi Steve,

Since 10.0 or so the Auto-Complete Polygon editing tool has been working pretty well for me.

And if that tool is not enough then topological editing is the way to go.

Filip.

Re: How can I auto-connect polygons in ArcGIS 10.3?

SteveSkotnicki — Wed, 17 Jun 2015 21:10:54 GMT

I just tried the Auto Complete tool. It works, at least for two relatively simple polygons. My GIS coworker also recommends the cutting-polygon technique. I will try both, and play with the typology and see what works best for me. If I have any insights I'll post them.

Darren, Ian, Wes, Stephe, and Filip, I am grateful for your advice:)

Re: How can I auto-connect polygons in ArcGIS 10.3?

BruceCarroll1 — Thu, 18 Jun 2015 16:06:09 GMT

I use the cut larger polygon method suggested by Darren when I can. It is definitely the most efficient and leads to fewer gap and overlap errors.

Another couple of techniques that I use:

1) use the Trace tool to trace coincident boundaries, then end the trace to digitize the non-coincident boundaries

2) turn vertex snapping on (Editor - Snapping - Snapping Window, click on Edit Sketch and Edit Sketch Vertices). Then, as you are digitizing, hold the V key down which will highlight the vertices making it easier to click on the exact location so that the lines coincide

Re: How can I auto-connect polygons in ArcGIS 10.3?

SteveSkotnicki — Thu, 18 Jun 2015 16:42:35 GMT

Bruce, doesn't this mean you need to, in effect, draw/trace the same edge twice?

Re: How can I auto-connect polygons in ArcGIS 10.3?

JayHanson — Thu, 18 Jun 2015 17:05:02 GMT

All so you can look into using the "align to shape" to in the Advanced editing tool bar.

Re: How can I auto-connect polygons in ArcGIS 10.3?

BruceCarroll1 — Thu, 18 Jun 2015 17:13:14 GMT

Steve, Yes indeed. That is why I mentioned that the "cut larger polygon" was the most efficient. But sometimes you have to deal with the hand you are dealt (Shapefile or Geodatabase).

Re: How can I auto-connect polygons in ArcGIS 10.3?

SteveSkotnicki — Thu, 18 Jun 2015 21:25:58 GMT

Thanks Jay.

Being new to GIS, and after working on this for about 8 hours, I agree with you that the cut-polygons method is easiest. However, in order for it to work, ALL adjacent polygons must be selected, not just the one I am working on. I have also had success occasionally stopping and using both the polygon tool (for closed isolated polygons) and the Auto-complete Polygon tool for two adjacent polygons not near the edge of the map.

So I am going to consider this question answered. Thanks very much for your help:)

Re: How can I auto-connect polygons in ArcGIS 10.3?

tMarkWilliams — Fri, 19 Jun 2015 08:24:51 GMT

Hi Steve

I just thought I would add, that you could add lines with snapping turned on and then at the end convert Features to Polygons

Hope this helps

Mark

"Bring back the coverage!", (R. West 2002)

Re: How can I auto-connect polygons in ArcGIS 10.3?

SteveSkotnicki — Fri, 26 Jun 2015 16:31:08 GMT

Mark,

That's a good idea. If I do that, do all of the features ned to be lines, or can I later select only the only the lines I want to convert?