BUG: Series.diff does no arg validation unlike df.diff for `periods` · Issue #56607 · pandas-dev/pandas (original) (raw)

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Reproducible Example

In [1]: import pandas as pd df = In [2]: df = pd.DataFrame()

In [3]: df.diff(0.5)

ValueError Traceback (most recent call last) in ?() ----> 1 df.diff(0.5)

~/.miniconda3/envs/snowpark/lib/python3.8/site-packages/pandas/core/frame.py in ?(self, periods, axis) 9216 is_float(periods) 9217 # error: "int" has no attribute "is_integer" 9218 and periods.is_integer() # type: ignore[attr-defined] 9219 ): -> 9220 raise ValueError("periods must be an integer") 9221 periods = int(periods) 9222 9223 axis = self._get_axis_number(axis)

ValueError: periods must be an integer

In [4]: series = pd.Series() :1: FutureWarning: The default dtype for empty Series will be 'object' instead of 'float64' in a future version. Specify a dtype explicitly to silence this warning. series = pd.Series()

In [5]: series.diff(0.5) Out[5]: Series([], dtype: float64)

In [6]: df.diff('1')

ValueError Traceback (most recent call last) in ?() ----> 1 df.diff('1')

ValueError: periods must be an integer

In [7]: series.diff('1') Out[7]: Series([], dtype: float64)

In [8]: series.diff('a')

ValueError Traceback (most recent call last) Cell In[8], line 1 ----> 1 series.diff('a')

File ~/.miniconda3/envs/snowpark/lib/python3.8/site-packages/pandas/core/series.py:2903, in Series.diff(self, periods) 2818 @doc( 2819 klass="Series", 2820 extra_params="", (...) 2866 ) 2867 def diff(self, periods: int = 1) -> Series: 2868 """ 2869 First discrete difference of element. 2870 (...) 2901 {examples} 2902 """ -> 2903 result = algorithms.diff(self._values, periods) 2904 return self._constructor(result, index=self.index).finalize( 2905 self, method="diff" 2906 )

File ~/.miniconda3/envs/snowpark/lib/python3.8/site-packages/pandas/core/algorithms.py:1699, in diff(arr, n, axis) 1679 def diff(arr, n: int, axis: int = 0): 1680 """ 1681 difference of n between self, 1682 analogous to s-s.shift(n) (...) 1696 shifted 1697 """ -> 1699 n = int(n) 1700 na = np.nan 1701 dtype = arr.dtype

ValueError: invalid literal for int() with base 10: 'a'