I am assuming you are using ArcGIS 10.1 with this answer. I also assume that there is a 1:1 relationship between the two feature classes, that they are both in a geodatabase, that they have the same spatial reference, and that they are already sorted in the same order. I assume that if the buffers of two pairs of features do not intersect at all that you do not care about that information being output. If any of this is not true then some adjustments will need to be made.
This script will create a pair of buffered polygon feature classes as well as an intersection feature class and will attribute it with the percent overlap between pairs of features as well as FIDs for joining back to the buffered polygon feature classes (or your original lines if they share the same FIDs). The pairing of features is only made by simultaneously iterating over both of the buffered polygon feature classes (using itertools.izip) and assuming that they are pre-sorted and 1:1. I do have an assertion that will result in an error message if the values of the common key field you mentioned are not equal.
The if __name__ == "__main__": section is where you configure the script using your own data. This is a common way to test functions in a Python module.
import arcpy, os, itertools
def computeIntersectOverlapPairs(feature_class_1, key_field_1, feature_class_2, key_field_2, output_feature_class, buffer_distance):
desc = arcpy.Describe(feature_class_1)
buffer1 = arcpy.Buffer_analysis(feature_class_1, os.path.join(os.path.dirname(output_feature_class), "{0}_Buffer".format(os.path.basename(feature_class_1))), buffer_distance)
buffer2 = arcpy.Buffer_analysis(feature_class_2, os.path.join(os.path.dirname(output_feature_class), "{0}_Buffer".format(os.path.basename(feature_class_2))), buffer_distance)
createOutputFC(output_feature_class, desc.SpatialReference)
with arcpy.da.SearchCursor(buffer1, ["OID@", "SHAPE@", key_field_1]) as rows1:
with arcpy.da.SearchCursor(buffer2, ["OID@", "SHAPE@", key_field_2]) as rows2:
with arcpy.da.InsertCursor(output_feature_class, ["SHAPE@", "FID_1", "FID_2", "OVERLAP"]) as outrows:
for row1, row2 in itertools.izip(rows1, rows2):
assert row1[2] == row2[2], "Key values must be equal! (FID1: {0}, FID2 {1}, Key1: {2}, Key2: {3})".format(row1[0], row2[0], row1[2], row2[2])
shape1 = row1[1]
shape2 = row2[1]
if not shape1.disjoint(shape2):
intersect_shape = shape1.intersect(shape2, 4)
percent_overlap = (intersect_shape.area / (shape1.area + shape2.area)) * 100
outrows.insertRow((intersect_shape, row1[0], row2[0], percent_overlap))
def createOutputFC(path, spatial_reference=None):
arcpy.CreateFeatureclass_management(os.path.dirname(path), os.path.basename(path), "POLYGON", spatial_reference=spatial_reference)
arcpy.AddField_management(path, "FID_1", "LONG")
arcpy.AddField_management(path, "FID_2", "LONG")
arcpy.AddField_management(path, "OVERLAP", "DOUBLE")
if __name__ == '__main__':
arcpy.env.overwriteOutput = True
inputfc1 = r"C:\GISData\test8.gdb\atlantic_hurricanes_2000_lines"
inputfc2 = r"C:\GISData\test8.gdb\atlantic_hurricanes_2000_lines_shifted"
outputfc = r"C:\GISData\test8.gdb\atlantic_hurricanes_2000_lines_overlap"
field1 = "EVENTID"
field2 = "EVENTID"
bufferdist = 0.1
computeIntersectOverlapPairs(inputfc1, field1, inputfc2, field2, outputfc, bufferdist)
Visual analysis
Input Lines:
Buffered Lines:
Overlapping Area (~12% in this case):
