[GIS] Removing portion of attribute string

arcgis-10.2arcgis-desktopfield-calculator

I have done a bunch of internet research on this topic with no such luck. The closest I got to a solution is Removing extra string from text column in Attribute Table to make numeric column from number part using ArcGIS Field Calculator?.

I have an attribute field "UniqueID" with information formatted as "NE_MH143". other information in this field start with "SE_", "NW_" and "SW_". I would like to reduce this information to remove the first three characters of the string.

Can this be done with ArcGIS field calculator?

Best Answer

To strip off the first 3 characters simply use the following in a field calculation:

!UniqueID![3:]

Related Solutions

ArcGIS Desktop – Removing Numeric Characters from Alphanumeric Field

I would use regular expressions. If you put the following in the code block section of the calculator it will return a string that has all digits stripped, no matter were they are:

import re
def strip_digits(s):
    return re.sub("\d+", "", s)

This can then be called from the calculate box as:

strip_digits(!column_name!)

If you want to replace characters, add another argument to the function for the replacement characters, and put it in place of the empty string.

Remove Newline Character Python – Removing Return/Newline Character from Field Using Python

I think this is just a bug/limitation of the Python parser with the field calculator/Calculate Field tool. If a newline is encountered within the text field, a SyntaxError: EOL while scanning string literal occurs no matter what you try.

I can reproduce the issue at 10.1 SP1 by importing the following CSV file into a file geodatabase, adding a field and simply attempting to copy the Text field to the new field using the Field Calculator with the Python parser and and the expression !Text!.

ID,Text
1,"this is a multiline 
example"

Try switching to the VB parser, or using an UpdateCursor and avoiding the Field Calculator entirely.

This issue is also discussed on the ESRI forums, with the same conclusions:

End-of-line (EOL) Problem

The only relevant NIM I could find was this:

NIM085499 - CalculateField calculations using non-ASCII characters fail on a Linux engine with: "ERROR 000539: SyntaxError: EOL while scanning string literal (, line 1)".

Best Answer

Related Solutions

ArcGIS Desktop – Removing Numeric Characters from Alphanumeric Field

Remove Newline Character Python – Removing Return/Newline Character from Field Using Python

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