[0.24.0rc1] passing dtype='M8' to Index raises · Issue #24753 · pandas-dev/pandas (original) (raw)

ValueError Traceback (most recent call last) in ----> 1 pd.Index([], dtype='M8')

~/Envs/dask-dev/lib/python3.7/site-packages/pandas/core/indexes/base.py in new(cls, data, dtype, copy, name, fastpath, tupleize_cols, **kwargs) 306 else: 307 result = DatetimeIndex(data, copy=copy, name=name, --> 308 dtype=dtype, **kwargs) 309 return result 310

~/Envs/dask-dev/lib/python3.7/site-packages/pandas/core/indexes/datetimes.py in new(cls, data, freq, start, end, periods, tz, normalize, closed, ambiguous, dayfirst, yearfirst, dtype, copy, name, verify_integrity) 301 data, dtype=dtype, copy=copy, tz=tz, freq=freq, 302 dayfirst=dayfirst, yearfirst=yearfirst, ambiguous=ambiguous, --> 303 int_as_wall_time=True) 304 305 subarr = cls._simple_new(dtarr, name=name,

~/Envs/dask-dev/lib/python3.7/site-packages/pandas/core/arrays/datetimes.py in _from_sequence(cls, data, dtype, copy, tz, freq, dayfirst, yearfirst, ambiguous, int_as_wall_time) 366 data, dtype=dtype, copy=copy, tz=tz, 367 dayfirst=dayfirst, yearfirst=yearfirst, --> 368 ambiguous=ambiguous, int_as_wall_time=int_as_wall_time) 369 370 freq, freq_infer = dtl.validate_inferred_freq(freq, inferred_freq,

~/Envs/dask-dev/lib/python3.7/site-packages/pandas/core/arrays/datetimes.py in sequence_to_dt64ns(data, dtype, copy, tz, dayfirst, yearfirst, ambiguous, int_as_wall_time) 1704 inferred_freq = None 1705 -> 1706 dtype = _validate_dt64_dtype(dtype) 1707 1708 if not hasattr(data, "dtype"):

~/Envs/dask-dev/lib/python3.7/site-packages/pandas/core/arrays/datetimes.py in _validate_dt64_dtype(dtype) 1991 raise ValueError("Unexpected value for 'dtype': '{dtype}'. " 1992 "Must be 'datetime64[ns]' or DatetimeTZDtype'." -> 1993 .format(dtype=dtype)) 1994 return dtype 1995

ValueError: Unexpected value for 'dtype': 'datetime64'. Must be 'datetime64[ns]' or DatetimeTZDtype'.

We want that to raise eventually; ns precision should be specified. But we should maybe deprecate the old behavior first?

The best place to do it is probably before we get to arrays, so in DatetimeIndex.__new__ we can check for M8 specifically, warn, then pass through M8[ns].

It's less clear what we should do for something like M8[us]. In the past, we used to ignore the precision

this should arguably raise now...