Skip to main content
`Ctrl`+`K`

# pandas.errors.SpecificationError

exception pandas.errors.SpecificationError

  Exception raised by `agg` when the functions are ill-specified.

  The exception raised in two scenarios.

  The first way is calling `agg` on a Dataframe or Series using a nested renamer (dict-of-dict).

  The second way is calling `agg` on a Dataframe with duplicated functions names without assigning column name.

  Examples

      >>> df = pd.DataFrame({'A': [1, 1, 1, 2, 2],
      ...                    'B': range(5),
      ...                    'C': range(5)})
      >>> df.groupby('A').B.agg({'foo': 'count'})
      ... # SpecificationError: nested renamer is not supported

      >>> df.groupby('A').agg({'B': {'foo': ['sum', 'max']}})
      ... # SpecificationError: nested renamer is not supported

      >>> df.groupby('A').agg(['min', 'min'])
      ... # SpecificationError: nested renamer is not supported