Field Calculator runs without error, but does not populate desired fields

Question

I have merged numerous datasets that have the same attributes in different fields. I have TotalAcres, Total_Acres_Burned, TTL_ACRS, etc... I am trying to use field calculator to populate one field (TotalAcres) with all the acres values from the varying fields.

Using ArcMap 10.4.1 and python as parser.

Here is my code

def updateAcres ( TTL_ACRES, TotalAcres, ContrAcres, FIRE_SIZE, Field9, 
Total_Acres_Burned):
  if TTL_Acres > 0:
    TotalAcres = TTL_Acres
  elif ContrAcres > 0:
    TotalAcres = ContrAcres
  elif FIRE_SIZE > 0:
    TotalAcres = FIRE_SIZE
  elif Field9 > 0:
    TotalAcres = Field9
  elif Total_Acres_Burned > 0:
    TotalAcres = Total_Acres_Burned
  else: 
    return TotalAcres

Then my CodeBlock is: TotalAcres= !TotalAcres!

It runs without throwing an error but it does not populate TotalAcres with the value from any of the other Acres fields.

Any ideas?

Answer 1

You need to use the return method to write the new data to the field.

Pre-logic script code:

def updateAcres ( TTL_ACRES, TotalAcres, ContrAcres, FIRE_SIZE, Field9, 
    Total_Acres_Burned):
      if TTL_Acres > 0:
        return TTL_Acres
      elif ContrAcres > 0:
        return ContrAcres
      elif FIRE_SIZE > 0:
        return FIRE_SIZE
      elif Field9 > 0:
        return Field9
      elif Total_Acres_Burned > 0:
        return Total_Acres_Burned
      else: 
        return TotalAcres

function to call:

updateAcres(!TTL_ACRES!, !TotalAcres!, !ContrAcres!, !FIRE_SIZE!, !Field9!, 
!Total_Acres_Burned!)