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I am having a difficulty with creating polyline feature from a point dataset that represents a boundary. This dataset consists of 5084 points which are randomly ordered. I have no Network Analyst extension available. I tried to use X Tools Pro and 'Make Polylines from Points' tool, but not having the right drawing order set up the output is just a random cross of polylines.

I have also tried 'Tracing' in the edit session but I've found that it wasn't possible to trace points (only lines or polygons) - please correct me if I'm wrong.

PolyGeo
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Magda
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    You will find these related threads informative: http://gis.stackexchange.com/questions/1200/concave-hull-definition-algorithms-and-practical-solutions (concave hulls and "alpha shapes"); http://gis.stackexchange.com/questions/5426/how-to-find-the-boundary-co-ordinates-from-a-given-set-of-co-ordinates (convex hulls). Long ago I contributed a solution on the ESRI site which exploits the observation that many polygons are star-shaped with respect to their centers; it therefore connects the points in order of their angles around their centroid. – whuber Feb 07 '12 at 17:52
  • That "connect the dots" is really cool, we need that rewritten in Python for ArcGIS. Maybe I'll tackle it sometime. – klewis Feb 09 '12 at 04:43
  • "I've found that it wasn't possible to trace points" - an option is to use Snapping to make this slightly easier. It still wouldn't be much fun with 5,084 points though... – Stephen Lead Aug 06 '12 at 02:17

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It sounds like the solution to your problem might require a different approach (based on @whuber's comment) but I have previously seen that a Shapefile's drawing order is based on the order the features are written to the file.

If you have access to FME (or a trial of it) you can use the Sorter transformer to sort by any single or combination of attributes before writing to a file. There are probably other (perhaps cheaper) ways to change the writing order but having access to FME I've never had to look.

tomfumb
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Perhaps using lat/long (x/y) to order will allow to use the points to line tool with the lat or long as the drawing order. Then you can go back and manually verify the line and fix any zig-zags that aren't correct. If your points don't run all east/west or north/south then maybe you can do it in segments.

Justin
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