Create Polygon from Polyline and seperate polygon feature

PBSEngineering_and_Environment — Mon, 09 Apr 2012 18:54:51 GMT

I have a some GPS data coming back from a field crew that I need to make into polygons and was wondering if folks could help with a streamlined approach.

Work is being collected with Trimble GPS, was supposed to use a data dictionary, but instead field crew has been creating generic points and generic polylines (long story, not worth fighting the fight at this point).

Background is, field crews are delineating wetlands within a Right-of-Way (ROW). Where the wetland leaves the ROW the crew does not have access. Therefore, in many cases the result is a polyline that is basically a three sided feature. I want the fourth side (assume for simplicity we are talking about rectangles) to be the ROW boundary. Upwards of 175 features are delineated to date so manually snapping to the ROW edge will be a bit tedious.

What might be some suggestions for a process to create polygons that will be bound by the ROW?

Thanks in advance for any suggestions.

(Oh, using ArcView license)

-Chris

Re: Create Polygon from Polyline and seperate polygon feature

HardolphWasteneys — Mon, 09 Apr 2012 23:25:05 GMT

Chris,

I've used Trimble GeoXTs with ArcPAD for geological mapping and routinely collected the data as several separate polyline feature classes with various attributes and points for a variety of geological observations. I loaded the data onto a workstation where I created polygons delineated by the various polyline features and directly from them.

From what you describe I presume you have a large polygon feature (the ROW) within which you have GPS created polylines for the wetland boundaries that continue across the ROW boundary.   There are several ArcView 9.2, 9.3, 10 options for creating polygons directly from polylines as well as creating polylines from polygons. The general idea would be to first create a polyline from the border of the ROW then complete a polygon for each wetland using that boundary and the polyline edges of the wetlands. You can set the whole works up and do it in one operation to create polygons for all the wetlands.

I routinely use the auto-complete polygon Task to create polygons from multiple polyline feature classes in ArcView 9.3 (also works in 9.2 and 10). This involves copying and pasting the polyline features into a scratch feature class and merging them, then running Auto-complete with a few tricks similar to the method described for splitting polygons using existing lines.   I've posted variations on the method several times http://forums.arcgis.com/threads/6288-Editing
http://forums.arcgis.com/threads/518...5524#post15524

Here's the step by step procedure I use (previously posted and edited):

1. start by making sure the line segments are either snapped together or overlap (optionally, set snapping in the polyline layers that you want to use).
Any existing polygons present within the area of interest (your ROW polygon) will create holes in the generated polygon fabric so turn those layers off.
I set up a scratch polyline feature class in the current workspace/geodatabase for temporary use to avoid messing with the original field data or attributed and symbolized polylines.

2. select all the polyline segments with the edit tool or by any select by attribute method in the attribute table (these can be in multiple workspaces/geodatabases as long as they are selectable)
3. set Task: Create New Feature and Target: the scratch polyline Feature Class
4. right click with the edit tool in the work area and hit copy, then right click again and hit paste (this creates a set of unattributed lines in the scratch feature class and deselects the ones selected from the original feature classes; ctrl-c, ctrl-v won't work for this ).
5. In the EDITOR pulldown menu hit MERGE, and use any of the lines as the one to be merged with.
6. leaving the merged line selected change "Target:" to a polygon FC and "Task:" to "Auto-complete Polygon"
7. using the SKETCH tool allow it to snap to the selected merged line anywhere (do not left click) and RIGHT-click and select "replace sketch" from the pull-down menu.
8. all the vertices of all the lines should become highlighted; hit F2 or right-click again and hit Finish Sketch.

For map display purposes I then overlay the original polylines with their variable symbology as the borders for the polygons.

Here's a couple of recent threads where I outlined some similar methods if that isn't explicit enough:

http://forums.arcgis.com/threads/678...hlight=polygon
http://forums.arcgis.com/threads/269...hlight=polygon
http://forums.arcgis.com/threads/306...hlight=polygon
http://forums.arcgis.com/threads/51008-Unable-to-construct-polygons-from-lines-in-ArcGIS-10
Replies to that thread indicate it works in 10 as well as 9.3.

The method for creating a polyline from the ROW polygon involves a script that creates a text file of the polygon vertices and then simple text edit in the resulting file substituting the header Polyline for Polygon and running the Create Feature from Text script on the saved file to make the polyline.
http://resources.esri.com/help/9.3/ArcGISDesktop/com/Gp_ToolRef/data_management_samples_tools/create_features_from_text_file_samples_.htm   or http://resources.esri.com/geoprocessing/index.cfm?fa=codeGalleryDetails&scriptID=15945

After creating the polygons I would then attribute them from the point features lying within them using the Attribute Transfer Tool.

good luck,

Hardolph

Re: Create Polygon from Polyline and seperate polygon feature

PBSEngineering_and_Environment — Wed, 11 Apr 2012 17:06:21 GMT

Hardolp,

Thank you for the reply. I was reading some of your previous posts this morning on similar topics.

There is a lot to digest so I will start experimenting this morning.

Thanks again for your time and suggestions!

-Chris-

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Create Polygon from Polyline and seperate polygon feature

Re: Create Polygon from Polyline and seperate polygon feature

Re: Create Polygon from Polyline and seperate polygon feature