"else" doesn't work correctly after seris of if/elif statements

clt_cabq

I have some code that classifies features based on a combination of landuse and "points" assigned across three variables. In running this code, there are 4 classification values to assign, with the last being a catch-all for some miscellaneous cases. I am iterating through a dictionary that holds values for land use, and upper and lower point value limits that affect the classification. I tried using a sequence of if/elif/elif/else statements and if I run it this way, everything gets assigned the catch-all value but if I drop the else statement at the end the code classifies everything correctly except for the miscellaneous features which remain null. Any thoughts as to what is happening? I've found an alternative solution to this but am curious why this approach fails.

field_list = ['LandUse','APD_Points','AFR_Points','CED_Points','TotalPoints','Program']
prop_dict = {'undev':('Undeveloped',10, 20), 'res':('Residential',15,30),'mfam':('Multifamily',80,160),'NR':('Non Residential',40,80),'ED':('Education Facility'),'EX':('Exclude')}
# iterate through dictionary and update attributes with classifcation values based on point ranges and landuse category
for in_arg in prop_dict.values():
    ptype = in_arg[0]
    llimit = in_arg[1]
    ulimit = in_arg[2]
    with arcpy.da.UpdateCursor(fc,field_list) as cursor:
        for row in cursor:
            if (row[0] == ptype and row[2]+row[3] > 0 and (row[1]>=llimit)):
                row[5] = 'PGM1 Qualifying'
            elif (row[0] == ptype and row[1]>= ulimit):
                row[5] = 'PGM2 Qualifying'
            elif (row[0] == ptype and row[1] < ulimit):
                row[5] = 'Non-Qualifying'
            else:
                row[5] = 'Public'
            cursor.updateRow(row)

  

blake.terhune

I think the problem is that you're doing two different iterations together, possibly causing everything to get overwritten with whatever comes last. Instead of iterating the cursor rows inside of iterating the dictionary, just look up the values in the dictionary for each row.

 

field_list = [
    'LandUse',
    'APD_Points',
    'AFR_Points',
    'CED_Points',
    'TotalPoints',
    'Program'
]
prop_dict = {
    'Undeveloped': {'llimit': 10, 'ulimit': 20},
    'Residential': {'llimit': 15, 'ulimit': 30},
    'Multifamily': {'llimit': 80, 'ulimit': 160},
    'Non Residential': {'llimit': 40, 'ulimit': 80},
    # 'Education Facility': {'llimit': ?, 'ulimit': ?},
    # 'Exclude': {'llimit': ?, 'ulimit': ?},
}

with arcpy.da.UpdateCursor(fc, field_list) as cursor:
    for row in cursor:
        limits = prop_dict.get(row[0])
        if limits:
            llimit, ulimit = limits.values()
            if row[1] >= llimit and row[2] + row[3] > 0:
                row[5] = 'PGM1 Qualifying'
            elif row[1] >= ulimit:
                row[5] = 'PGM2 Qualifying'
            elif row[1] < ulimit:
                row[5] = 'Non-Qualifying'
            else:
                row[5] = 'Public'
        else:
            print(f"'{row[0]}' is not defined in prop_dict")
            row[5] = 'Public'

        cursor.updateRow(row)