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I have a float field which I want to simply update all values with 1. I can easily do this within the field calculator but I have started using python today, what is the syntax to simply update a field with the value 1. I'm stuck on the expression bit of the script:


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up vote 3 down vote accepted

Looking at the ArcGIS help section, you can see the necessary parameters and descriptions:

CalculateField_management (in_table, field, expression, {expression_type}, {code_block})

To translate this to your script;

import arcpy

file = r'C:\your\file.shp'

arcpy.CalculateField_management (file, "FRMEAS", "1")
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Thanks, I was thinking into it to much by doing =1 or "!FRMEAS! = 1" – Alan Carr Apr 3 '14 at 16:10
@Aaron if it's a float field, do you have to put the 1 in quotes? – ianbroad Apr 3 '14 at 16:12
It is optional @ian – Aaron Apr 3 '14 at 16:16

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