I have a polygon feature that is 228 miles in length and 95 feet in width. But, along the polygon there are sections that are 75 feet wide. I was tasked with locating those sections and flagging them. I tried to look thorough the different ArcMap toolbox options and could not find an appropriate tool that might get me the results I need. I suspect I need to use some creativity and a combination of tools to achieve that goal. Any suggestions?
As @FelixIP suggested the following method and steps answered my question above:
- I converted the polygon shape into two polylines using the "Polygon To Line" tool, added a field to the attribute table and gave each line a unique name/ID.
- I converted the lines into points using the "Generate Points Along Lines" tool with intervals of 50 feet (I'll add a note on that at the end of this post).
- I used the "Near" analysis tool to calculate the nearest point from one set of points to the second set of points.
- The result I got is the nearest point in one dataset to the other dataset (in my case, North_Points and South_Points).
- To find the narrowest parts of the original polygon shape I sorted the "Near_DIST" column by Ascending order.
Even thought my poylgon contain two width sizes: 95 feet and 75 feet, I can now easily identify the areas where the polygon gets "slimmer". And obviously, there are some exceptions here and there but overall this method worked for me.
Important note: the interval of points that being generated is VERY IMPORTANT. In my case, my polygon (or two polylines) were 228 miles in length and generating points every 50 feet took a while. But the smaller the interval is the more accurate results you will get because the points being generated are not directly against each other as you can see from the attached image. The two lines that that were generated from the polygon maybe are the same length in total, but the distance measurement changes as they twist and turn along the way if that make sense. If you have two parallel lines with the same exact length all your point would line-up.