How To: Create sequential numbers in a field using Python in the Field Calculator
Instructions provided describe how to create sequential numbers in a field using Python in the Field Calculator.
Note: The code in this article generates sequential numbers for unsorted data based on the OID or FID order. If the data is sorted on a field, the generated numbers will not be sequential.
- Create a new short integer field.
- Right-click the new field and select Field Calculator.
- Set the Parser to Python.
- Check the check box for Show Codeblock.
- Paste the following into the Pre-Logic Script Code:
rec=0 def autoIncrement(): global rec pStart = 1 pInterval = 1 if (rec == 0): rec = pStart else: rec += pInterval return rec
- Paste the following code in the smaller box below the Pre-Logic Script Code:
- Click OK. The following image is an example of a field with sequential numbers populated using the Python code:
- ArcMap Help: Adding fields
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- ArcMap Help: Calculate Field examples
Last Published: 6/27/2019
Article ID: 000011137