Replace Null Value - Field Calc, Python

KeithSoRelle

Trying to replace a null value with the field calculator. I am have a script that appends multiple feature classes into one feature class. After each feature class appends I want to add a field calculateField_management (field calculator) statement run that makes all null values from a specific field into a string value. 

I've tried a number of ways but have yet to get an expected result. 

I have 2 values for in the field - Null, 'CFW' and need to replace Null with 'TAR'.

Then I will have 3 values - Null, 'CFW', 'TAR' and will need to replace Null with 'DEN'

I've been trying something along the lines of:

 

def myCalc(x)

      if (x != 'CFW"):

         return 'TAR'

else:

      return 'CFW'

Should be simple but I haven't had much luck getting the expected response. Could use help on both field calculations.

Thanks,

-Keith 

JoshuaBixby

You can use Python Conditional expressions, a.k.a., ternary operators, to accomplish this task on one line.  Set the parser to Python and put the following in the expression box:

<SPAN class="string token">'TAR'</SPAN> <SPAN class="keyword token">if</SPAN> !Field! <SPAN class="keyword token">is</SPAN> None <SPAN class="keyword token">else</SPAN> !Field!<SPAN class="line-numbers-rows"><SPAN>‍</SPAN></SPAN>

Swap !Field! above for your field.