Trying to iterate through the a Layer and assign a list of Unique ID to a Field from attribute table

Question

Hello, I'm a beginner in ArcPy and I want to perform some tasks using ArcPy but I am not getting results. Using ArcMap I have an attribute field, with like 13K number of records. The Layer is called Splicepoint.

I would like to change the names of a fields in the attribute table called Station ID (to have a sequential name that I have created. In 11 character long name – SPLCNVA1A001, SPLCNVA1A002, SPLCNVA1A003…… SPLCNV1B001….. SPLCNV1Z001….. SPLCNV1Z999) They are all related to the field of SUBTYPE (FOSC). Also, I need to skip I and O’s to avoid confusion .

This is just a one time code that would keep changing the sequence.

JohannesLindner · Answer

Run this in the Python Window (change the first three lines):

fc = "TestPolygons"  # path to the feature class or name of the layer
field = "TextField1" # field you want to edit
sql = "Subtype = 'FOSC'" # select the features you want to edit

import string
letters = list(string.ascii_uppercase)
letters.remove("I")
letters.remove("O")

with arcpy.da.UpdateCursor(fc, field, sql) as cursor:
    for i, row in enumerate(cursor):
        letter = letters[int(i/1000)]
        number = i % 1000
        new_id = "SPLCNV1{}{:03}".format(letter, number)
        cursor.updateRow([new_id])

This will fail after Z999!

blake.terhune · Answer

@JMerryline wrote:I would like to change the names of a fields in the attribute table called Station ID (to have a sequential name that I have created.

Have you already coded the logic in Python to generate this sequential value?

JMerryline · Answer

On ArcMap Python window.

Yes I am starting with " with the first FOSC row and append the sequential number to the end of "SPLCNV" for the Station ID field value?"

okay so the pattern is

SPLCNV1A001,

SPLCNV1A002,

SPLCNV1A003……

SPLCNV1B001….. all the way to "Z"

SPLCNV1Z001…..

SPLCNV1Z999.... and eventually end at 1Z

SPLCN = SPLICE

NV = STATE which is Nevada

and then 1A and 001 (number up to 999)

THANK YOU.