topic Re: Joining lines (Create one line from multiple lines) in Transportation Questions

Joining lines (Create one line from multiple lines)

Mohammad_ShafayatHossain — Thu, 21 Mar 2013 21:54:42 GMT

Hello guys,

I have a polyline shapefile with hundreds of line segments. It�??s actually a city street network. But as the shape file was created from CAD file, not all the lines are continues where they should be. For example, if you look at the attached Exhibit-1, between node 1 and node 2, there are 4 different line segments (I colored the lines so that it�??s easy to understand). But I want to make those lines a single continuous line. That is, there should be only one connecting line segment between any two nodes/ intersections. Is there any way to do that? Your help would be highly appreciated.

Thanks
Shafayat

Re: Joining lines (Create one line from multiple lines)

JoshuaDamron — Mon, 25 Mar 2013 13:42:57 GMT

Yes, there is a relitively easy method to join/merge the segments - The Merge Tool!

The merge tool comes in a few differetn shapes and sizes. the ones I know about are:

If the features are all in the same feature class/shape file you can use this tool found in the Editor pull down menu: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//001t0000007q000000.htm (I fequently use this tool so I've added it as a button on my toolbars using Customize: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//002400000005000000.htm)

If your data is in different feature classes then you can use the Merge geoprocessing tool: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//001700000055000000

There's also a "Merge Divided Roads" tool, but I don't think it's what you are looking for: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00700000000w000000

If you have any other questions just post back!

Re: Joining lines (Create one line from multiple lines)

DanLee — Tue, 10 Dec 2013 15:20:02 GMT

Not sure if you have found a solution. You can try:
1. Use Dissolve tool to unsplit lines; if there is a street name field you can use that as the Dissolve Field.
2. If the resulting lines are crossing at intersections (not ending at intersections), you can use Feature To Line tool to break them at intersections.

Re: Joining lines (Create one line from multiple lines)

RichardFairhurst — Tue, 10 Dec 2013 23:22:43 GMT

Not sure if you have found a solution. You can try:
1. Use Dissolve tool to unsplit lines; if there is a street name field you can use that as the Dissolve Field.
2. If the resulting lines are crossing at intersections (not ending at intersections), you can use Feature To Line tool to break them at intersections.

I agree you need a Street name attribute to make this work correctly. Knuckle streets are not an uncommon type of intersection in a street network between two different roads, but most tools will only create an intersection if the point of connection will create 3 or more separate lines. Street Name attributes prevent knuckle streets from joining together.

I would consider using Create Routes rather than Dissolve if you have a street name field, since you can control more aspects of how the line in constructed and evaluate the result more fully with measure hatches. Measures that include gaps also can tell you if gap occur where you don't expect them, which can cause odd line chaining. Full loops will mess up every tool you could use, so beware of those.

If you don't have an Advanced license, the Planarize tool can divide lines at normal intersections as an alternative.