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I have a network of lines (pipes) and I want to be able to show the difference between an intersecting line and a crossing line. I was wondering if there is a tool for generating points on all crossings in ArcGIS. If I use "Intersect" I can find all intersecting and crossing points. I only need the crossing points.

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Have a look at Geometric Network in ArcGIS. I do not think that it'll be any of use in this case, though you may reconsider this for the future use for your networks. – Tomek Dec 15 '11 at 11:08
I know about Geometric Networks, but I don't see how this can be of use in any case like this? Am I missing something? – tmske Dec 15 '11 at 13:13
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Have you considered using a database topology with a rule saying that all line feature intersections must be covered by a point intersection feature, and treat the violations as crossings ? – Kirk Kuykendall Dec 15 '11 at 19:18
I am not using this feature that much but as far as I remember you build your network based on 2 data sets: segments (polylines) and junctions (points). Points are representing your x-sections. The tool seem to be designed for pipelines and other kind of networks. – Tomek Dec 16 '11 at 10:32

2 Answers

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After clarification:

You could try following steps: 1) Convert Feature Vertices to Points with the option point_location set to BOTH_ENDS 2) To the intersect you've already done previously 3) Use the Erase tool with output from previous steps at input

Old answer (for reference):

You could try to intersect with another tool like QGis because QGis doesn't do any self intersects. The difference of the intersect done with QGis with the intersect from ArcGIS should give you the crossing points.

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I don't think my question was entirely clear. With a crossing I mean two lines that in 2D visually intersect (but in reality they cross each other). An intersection for me is two or more lines that visually AND physically intersect (in reality there is and extra object like a T-junction), but we don't have these objects in the GIS. So we need to find the crossings and intersections with a tool. For the intersection there is always an endpoint on an other line on the intersection point. With a crossing there is no endpoint on crossing point. – tmske Dec 15 '11 at 13:48
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So junctions will have overlapping vertices, where as crossings do not. To find overlapping vertices you could ustilize ET Geowizard tool - Polyline to Point to convert only vertices to a new point layer. Then run the Intersect tool on the new point layer. This will leave you with a junction point layer.

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If I understand this correctly then you are suggesting to create a point from the end and start points of the line. These 2 points you would intersect with the lines. Then you have found all the intersections (we will find a lot more - 2 lines with different materials or diameter will also intersect but that's ok). We can then delete all overlapping points from the original intersection and that should leave the crossings. Will try this now, although I don't have the ET Geowizard, but I guess I can find the start-end points an other way too. – tmske Dec 15 '11 at 15:53
Normally you can use Convert Feature Vertices to Points with the option point_location set to BOTH_ENDS from ArcGIS to get the start-end points. – gissolved Dec 15 '11 at 16:07
You can use ET GeoWizard tools for free. Not sure about this function, but few of them are not limited at all and the rest can process upto 100 features in free version. – Tomek Dec 16 '11 at 10:36

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