Writing if/else statement in field calculator for calculating values

Brian_McLeer — Sun, 12 Dec 2021 10:52:01 GMT

I have referenced this article Writing conditional (if/then) statements into Field Calculator of ArcGIS for Desktop using Python parser? - Geographic I…

I am trying to update values in a field using 'elif' statements in Field Calculator with the Python radio button selected.

The set is as:

Code Block:

def Reclass(Density_18):
                if (Density_18 <= .8493):
                                return 1
                elif (Density_18 >.8493 and Density_18 <=1.761):
                                return 2
                elif (Density_18 >1.761 and Density_18 <=2.345):
                                return 3
                elif (Density_18 >2.345 and Density_18 <=3.399):
                                return 4
                elif (Density_18 >3.399):
                                return 5‍‍‍‍‍‍‍‍‍‍‍

Expression:

Reclass( !Index_18!)‍

When this expression is performed, it calculates all the values as '1', then the next time it is run all values are '2', so on until it maxes out and repeats at '5' in the Index_18 field.

Re: Writing if/else statement in field calculator for calculating values

DanPatterson_Retired — Sun, 12 Dec 2021 10:52:04 GMT

Indentation is a bit off, but I tested it after reformatting using individual values and it is fine.

I suspect that the !Index1! field is the field you are trying to put the values IN and not the field that contains the Density values... check that

Python parser, as before

def Reclass(Density_18):
    if (Density_18 <= .8493):
        return 1
    elif (Density_18 >.8493 and Density_18 <=1.761):
        return 2
    elif (Density_18 >1.761 and Density_18 <=2.345):
        return 3
    elif (Density_18 >2.345 and Density_18 <=3.399):
        return 4
    elif (Density_18 >3.399):
        return 5
    

Reclass(Density_18)
 3

Density_18 = .1

Reclass(Density_18)
1‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

topic Writing if/else statement in field calculator for calculating values in ArcGIS Pro Questions

Writing if/else statement in field calculator for calculating values

Re: Writing if/else statement in field calculator for calculating values