mapping does not work anymore

[thinkredot]

Hi, im trying to understand what is causing me my issue.It used to work!
Last time i ran this code was about a year ago
Is this python , pandas or streamlit ?
I have this code to map zips ( first 3 digits of the zips )

def area_zips(zipcode):
    zips = {"010": "Springfield", "011": "Springfield", "012": "Springfield", "013": "Springfield", "014": "Boston"}
    return zips[zipcode[:3]]
df["PuMarket"] = df["PuZip"].map(area_zips)
 

This code to map states:

    
def regions(region):
    states = {"ME": "Northeast", "NH": "Northeast"}
    return states[region]
df["PuRegion"] = df["PuState"].map(regions)

i get errors. Error sample for zip codes, but same errors if i remove zips and leave region code.

Error:
 KeyError: ''
Traceback:

File "/development/koala/lib/python3.12/site-packages/streamlit/runtime/scriptrunner/exec_code.py", line 88, in exec_func_with_error_handling
    result = func()
             ^^^^^^
File "/development/koala/lib/python3.12/site-packages/streamlit/runtime/scriptrunner/script_runner.py", line 590, in code_to_exec
    exec(code, module.__dict__)
File "/development/koala/1_Home.py", line 169, in <module>
    df = load_data()
         ^^^^^^^^^^^
File "/development/koala/lib/python3.12/site-packages/streamlit/runtime/caching/cache_utils.py", line 210, in __call__
    return self._get_or_create_cached_value(args, kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/development/koala/lib/python3.12/site-packages/streamlit/runtime/caching/cache_utils.py", line 235, in _get_or_create_cached_value
    return self._handle_cache_miss(cache, value_key, func_args, func_kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/development/koala/lib/python3.12/site-packages/streamlit/runtime/caching/cache_utils.py", line 288, in _handle_cache_miss
    computed_value = self._info.func(*func_args, **func_kwargs)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/development/koala/1_Home.py", line 102, in load_data
    df["PuMarket"] = df["PuZip"].map(area_zips)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/development/koala/lib/python3.12/site-packages/pandas/core/series.py", line 4700, in map
    new_values = self._map_values(arg, na_action=na_action)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/development/koala/lib/python3.12/site-packages/pandas/core/base.py", line 921, in _map_values
    return algorithms.map_array(arr, mapper, na_action=na_action, convert=convert)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/development/koala/lib/python3.12/site-packages/pandas/core/algorithms.py", line 1743, in map_array
    return lib.map_infer(values, mapper, convert=convert)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "lib.pyx", line 2972, in pandas._libs.lib.map_infer
File "/development/koala/1_Home.py", line 100, in area_zips
    return zips[zipcode[:3]]
           ~~~~^^^^^^^^^^^^^ 

Thank You.

[deanhystad]

Somewhere in your dataframe you have " " in the PuZip column.

This works:

import pandas as pd

def area_zips(zipcode):
    zips = {"010": "Springfield", "011": "Springfield", "012": "Springfield", "013": "Springfield", "014": "Boston"}
    return zips[zipcode[:3]]

df = pd.DataFrame({"PuZip": ["01000", "01100", "01200", "01300", "01400"]})
df["PuMarket"] = df["PuZip"].map(area_zips)
print(df)

Output:
   PuZip     PuMarket
0  01000  Springfield
1  01100  Springfield
2  01200  Springfield
3  01300  Springfield
4  01400       Boston

But if I add " " to PuZip:

df = pd.DataFrame({"PuZip": ["01000", "01100", "01200", "01300", "01400", " "]})

I get the same error you have.

Error:
  File "test.py", line 5, in area_zips
    return zips[zipcode[:3]]
           ~~~~^^^^^^^^^^^^^
KeyError: ' '

An easy way to find the bad line, and something you should always do, is provide a default value for when the map function fails.

def area_zips(zipcode):
    zips = {"010": "Springfield", "011": "Springfield", "012": "Springfield", "013": "Springfield", "014": "Boston"}
    return zips.get(zipcode[:3])

Now instead of a crash, I get a dataframe that has None

Output:
   PuZip     PuMarket
0  01000  Springfield
1  01100  Springfield
2  01200  Springfield
3  01300  Springfield
4  01400       Boston
5                None

If you don't like None, you can provide any default value you want for zips.get().

[dwellsteam]

It is hard to spot the issues. Thanks for sharing and updating the important information.