topic Re: Count Duplicates in a Field for sequential unique ID in ArcMap Questions

Count Duplicates in a Field for sequential unique ID

GabriellaSantana — Mon, 10 May 2021 23:45:53 GMT

I am trying to create a unique ID for my street feature class. (My unique ID starts with first 3 letters of the Street Name, 2 letters of the Street type, and 3 letters of the City Name Abbreviated.) Where I am stuck is that I am trying to get a number to increment on the segments that would be duplicated. For example, Glenacre Drive has three segments. The UniqueID would be GLEDRHQF01, GLEDRHQF02, GELDRHQF03. I cant figure out how to create sequential numbers not based off of the ObjectID sorting... For example I used the following Field Calculator but realized it is looking at the ObjectID sort and my streets aren't entered in order...

Pre-Logic Script Code:

prevFieldValue = '' counter = 1 def GetDuplicateCounter(myFieldValue): global prevFieldValue global counter if myFieldValue == prevFieldValue: counter += 1 else: counter = 1 prevFieldValue = myFieldValue return counter

= GetDuplicateCounter( !UNIQUEID! )

Any Help would be Amazing! 🙂

Re: Count Duplicates in a Field for sequential unique ID

JohannesLindner — Tue, 11 May 2021 07:46:43 GMT

Define a dictionary that relates the string part of the id to the corresponding counter:

duplicates = {"GLEDRHQF": 3} def get_duplicate_counter(value): try: counter = duplicates[value] + 1 except KeyError: counter = 1 duplicates[value] = counter return counter # or directly return the complete id: # return "{}{:02d}".format(value, counter)

Re: Count Duplicates in a Field for sequential unique ID

JoshuaBixby — Tue, 11 May 2021 13:56:39 GMT

Something like this should work in the interactive Python window:

lyr = # name of layer or path to data set with arcpy.da.UpdateCursor(lyr, "UNIQUEID", sql_clause=(None, "ORDER BY UNIQUEID")) as cur: cnt = 1 uid, = next(cur) cur.updateRow(["{}{:02}".format(uid,cnt)]) uid_prev = uid for uid, in cur: if uid == uid_prev: cnt += 1 else: cnt = 1 cur.updateRow(["{}{:02}".format(uid,cnt)]) uid_prev = uid

Re: Count Duplicates in a Field for sequential unique ID

GabriellaSantana — Tue, 11 May 2021 16:46:40 GMT

Thank you so much! Is there a way for me to make this create a new field and populate it?

Re: Count Duplicates in a Field for sequential unique ID

JoshuaBixby — Wed, 12 May 2021 01:36:43 GMT

Just use Add Field (Data Management)—ArcMap | Documentation (arcgis.com) upstream of the code snippet I provided, and then adjust the cursor to work with the necessary fields.

Re: Count Duplicates in a Field for sequential unique ID

GabriellaSantana — Wed, 12 May 2021 16:19:42 GMT

Thank you!!