Why does Python if/else statement only return else condition when trying to reclassify field using ArcMap field calculator?

Question

Using ArcGIS 10.4. I'm trying to reclassify values from a field (ECOREGION_DIVISION), which is in string format, into new values using the following Python syntax:
def Reclass(ECOREGION_DIVISION):
  if (ECOREGION_DIVISION == "Desert"):
    return "Not forest"
  else:
    return "Forest"
 
    Reclass(!ECOREGION_DIVISION!)

The result is that all the values in the new_class field are returned as "Forest" (the if statement does not return "Not forest" when value = "Desert"). The new_class field is also string format. Does this syntax seem correct?

kent · Answer

Solution:

I ended up creating a field of the class codes rather than the Ecoregion text as the input (as either a string or integer to test out). I made sure to create syntax according to the new fields (string vs integer). The Reclass function now classifies as either a text or number field (important to use quotes for the string).

Here is the python syntax for string reclass:

def Reclass(new_class):
  if new_class == "240":
    return "Marine"
  else:
    return "Not Marine"

Reclass( !new_class!)

And this is the syntax for a number reclass:

def Reclass(new_code):
  if new_code == 240:
    return 1
  else:
    return 2

Reclass( !new_code!)

I'm not exactly sure if the reason this works now is because I am using the class code field rather than the class field itself, or due to some other tweaking such as setting up correct field types.

Why does Python if/else statement only return else condition when trying to reclassify field using ArcMap field calculator?

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