Find crossing point of polyline layer

Question

I have a polyline layer. I want to split this polyline layer at CROSSING POINT. With two steps I want to do this.

1. I show the user the CROSSING POINT of polyline layer.
2. With this CROSSING POINT, I want to split the polyline layer.

I am on Arcgis 10 with .NET/arcpy. Second step can be done with SPLIT LINE AT POINT tool. But how can I identify the crossing point?

I have attached image to clear my problem.

Answer 1

I think I know what you mean, you should do that by 2 tools step by step first step find in arctoolbox intersect (Analysis) and then create intersect point layer in Intersection tools window choose "point" in output type field intersect(Analysis)

finally [Step2] by Split line at point tools in ArcToolbox you can split polyline based on intersection points

for example: Config your Intersection Tool window like below picture Config your Split Line At Point like below picture

Answer 2

Although there is already an accepted answer to this question, as it was tagged as arcpy, I'd like to add one open source alternative by using one equivalent tool: PyQGIS.

My polyline layer was very similar to above question:

Complete code is:

import itertools

layer = iface.activeLayer()

feats = [ feat for feat in layer.getFeatures() ]

n = len(feats)

list = range(n)

points = [ feats[i].geometry().intersection(feats[j].geometry()).asPoint()
           for i,j in itertools.combinations(list, 2)
           if feats[i].geometry().intersects(feats[j].geometry()) ]

lines = [ [ points[i], points[j] ] 
            for i,j in itertools.combinations(list, 2) ]

epsg = layer.crs().postgisSrid()

uri = "Point?crs=epsg:" + str(epsg) + "&field=id:integer""&index=yes"

mem_layer = QgsVectorLayer(uri,
                           'points',
                           'memory')

prov = mem_layer.dataProvider()

feats = [ QgsFeature() for i in range(len(points)) ]

for i, feat in enumerate(feats):
    feat.setAttributes([i])
    feat.setGeometry(QgsGeometry.fromPoint(points[i]))

prov.addFeatures(feats)

QgsMapLayerRegistry.instance().addMapLayer(mem_layer)

uri = "LineString?crs=epsg:" + str(epsg) + "&field=id:integer""&index=yes"

mem_layer = QgsVectorLayer(uri,
                           'lines',
                           'memory')

prov = mem_layer.dataProvider()

feats = [ QgsFeature() for i in range(len(lines)) ]

for i, feat in enumerate(feats):
    feat.setAttributes([i])
    feat.setGeometry(QgsGeometry.fromPolyline(lines[i]))

prov.addFeatures(feats)

QgsMapLayerRegistry.instance().addMapLayer(mem_layer)

After running it at the Python Console of QGIS, I got crossing points and split polyline layer: