Search code examples
pythonpandasdataframekeyerror

KeyError for an object value that is in the dataframe

Can someone explain why 'Louisville' is returning a KeyError? It is in the data frame from what I understand. What am I missing?

Here is what the data looks like. It is a CSV.

data

This is what off_data.head() looks like

off_data.head()

off_data.index()

off_data.index()

off_data.columns

off_data.columns

off_data[0:2].to_dict()

off_data[0:2].to_dict()

Rajith Thennakoon's Suggestion

Rajith Thennakoon's suggestion

{'Conf': {'Michigan St. ': 'B10', 'Louisville ': 'ACC'},
 'AdjTempo': {'Michigan St. ': 70.4, 'Louisville ': 67.8},
 'AdjOE': {'Michigan St. ': 114.4, 'Louisville ': 113.9},
 'eFG%': {'Michigan St. ': 52.9, 'Louisville ': 60.7},
 'TO%': {'Michigan St. ': 15.9, 'Louisville ': 17.1},
 'OR%': {'Michigan St. ': 37.1, 'Louisville ': 32.8},
 'FTRate': {'Michigan St. ': 30.9, 'Louisville ': 32.5},
 'AdjDE': {'Michigan St. ': 85.1, 'Louisville ': 87.5},
 'deFG%': {'Michigan St. ': 40.3, 'Louisville ': 42.9},
 'dTO%': {'Michigan St. ': 20.7, 'Louisville ': 15.9},
 'dOR%': {'Michigan St. ': 25.0, 'Louisville ': 27.6},
 'dFTRate': {'Michigan St. ': 27.3, 'Louisville ': 26.0}}

Input

import pandas as pd

off_data = pd.read_csv(r'C:\Users\westc\Desktop\sports.data\ncaab\kenpomdata\off20.csv', index_col= 'Team')

type(off_data)

off_data.loc["Louisville",0]

Output

KeyError Traceback (most recent call last) ~\Anaconda3\lib\site-packages\pandas\core\indexes\base.py in get_loc(self, key, method, tolerance) 2896 try: -> 2897 return self._engine.get_loc(key) 2898 except KeyError:

pandas_libs\index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas_libs\index.pyx in pandas._libs.index.IndexEngine.get_loc()

pandas_libs\hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

pandas_libs\hashtable_class_helper.pxi in pandas._libs.hashtable.PyObjectHashTable.get_item()

KeyError: 'Louisville'

During handling of the above exception, another exception occurred:

KeyError Traceback (most recent call last) in 4 5 type(off_data) ----> 6 off_data.loc["Louisville",0]

~\Anaconda3\lib\site-packages\pandas\core\indexing.py in getitem(self, key) 1416 except (KeyError, IndexError, AttributeError): 1417 pass -> 1418 return self._getitem_tuple(key) 1419 else: 1420 # we by definition only have the 0th axis

~\Anaconda3\lib\site-packages\pandas\core\indexing.py in _getitem_tuple(self, tup) 803 def _getitem_tuple(self, tup): 804 try: --> 805 return self._getitem_lowerdim(tup) 806 except IndexingError: 807 pass

~\Anaconda3\lib\site-packages\pandas\core\indexing.py in _getitem_lowerdim(self, tup) 927 for i, key in enumerate(tup): 928 if is_label_like(key) or isinstance(key, tuple): --> 929 section = self._getitem_axis(key, axis=i) 930 931 # we have yielded a scalar ?

~\Anaconda3\lib\site-packages\pandas\core\indexing.py in _getitem_axis(self, key, axis) 1848 # fall thru to straight lookup 1849 self._validate_key(key, axis) -> 1850 return self._get_label(key, axis=axis) 1851 1852

~\Anaconda3\lib\site-packages\pandas\core\indexing.py in _get_label(self, label, axis) 158 raise IndexingError("no slices here, handle elsewhere") 159 --> 160 return self.obj._xs(label, axis=axis) 161 162 def _get_loc(self, key: int, axis: int):

~\Anaconda3\lib\site-packages\pandas\core\generic.py in xs(self, key, axis, level, drop_level) 3735 loc, new_index = self.index.get_loc_level(key, drop_level=drop_level) 3736
else: -> 3737 loc = self.index.get_loc(key) 3738 3739 if isinstance(loc, np.ndarray):

~\Anaconda3\lib\site-packages\pandas\core\indexes\base.py in get_loc(self, key, method, tolerance) 2897 return self._engine.get_loc(key) 2898 `

Solution

  • You can get the row by:

    off_data.loc[off_data['Team'] == "Louisville"]

    The way your doing the location, requires the column name, which by your output appears to be Team, you could try these to see if they work:

    In [4496]: df2.loc[0,"Team"]                                                                                                                                                   
Out[4496]: 'Michigan'

In [4497]: df2.loc[1,"Team"]                                                                                                                                                   
Out[4497]: 'Louisville'

    Looks like there is whitespace in the data, here's a quick way to strip the whitespace at the end:

    off_data.index = off_data.index.str.strip()

    which should let you do a search as is:

    off_data[off_data.index == 'Louisville']