Creating dictionary of link and its adjacent links (having common vertex) in ArcPy

Question

How do I create a dictionary that has the linkID of a link as key and linkID of touching links as values?

I have used this code in ArcPy but it takes a very long time.

arcpy.CopyFeatures_management(link,link1)
arcpy.MakeFeatureLayer_management(link,"link")
arcpy.MakeFeatureLayer_management(link,"link1")

fid_fid_dict = {} #the dictionary that has linkID and its connecting linkIDs

with arcpy.da.SearchCursor(link, ["FID"]) as curs:
    for row in curs:
        arcpy.SelectLayerByAttribute_management("link", "NEW_SELECTION", '"FID" = {}'.format(row[0])) #selects a link
        arcpy.SelectLayerByLocation_management('link1', "INTERSECT", "link", "", "NEW_SELECTION") #selects touching links
        fid_fid_dict[row[0]] = [_row_[0] for _row_ in arcpy.da.SearchCursor("link1", ['FID'])] #gets the IDs of touching links

The final dictionary should be:

dict = {linkID:[linkID1, linkID2, linkID3, linkID4]}

Answer 1

I think some of things you can try to speed up the processing.

1. Use Spatial Indices. This is default if your data is in a geodatabase, but if you are using shapefiles you should create an index.

2. Loading data into memory can improve performance.

3. Reducing the number of select calls as these can be slow.

Here is some code to try and see if it helps improve the process.

links = [ (row[0],row[1]) for row in arcpy.da.SearchCursor(link,["OID@","SHAPE@"])]
links = arcpy.CopyFeatures_management(link,r"in_memory\links1")
fid_fid_dict = {k:[] for k,g in links}
for fid,geom in links:
    arcpy.SelectLayerByLocation_management("links1","INTERSECT",geom,"","NEW_SELECTION")
    fid_fid_dict[fid] = [row[0] for row in arcpy.da.SearchCursor("Links1",["OID"])]