DEPR: let's deprecate

xref #18202

We have some cruft, let’s deprecate it (I have noted some which already have an issue associated).

From ndarray

• Series.compress() (#21930)
• Series.imag / Series.real (#27106)
• Series.nonzero() (#24048)
• Series.put() (#27106)
• Series.itemsize
• Series.flags
• Series.strides

timeseries specific

• Series.first() let head / tail take a timedelta
• Series.last()

other

• Series.swapaxes()
  • No reason once panel is gone.

non-controversial

• MultiIndex.to_hierarchical (only used for Panel) (#21613)
• Series/DataFrame.compound() (#26405)
• Series.ptp() (#21614)
• Series.from_array (#18213)
• Series.valid() (#18800)
• Series/DataFrame.slice_shift() (#37601)
• Series/DataFrame.tshift() (https://github.com/pandas-dev/pandas/pull/34545)
• Series/DataFrame.get_values() (https://github.com/pandas-dev/pandas/issues/19617)
• Index.dtype_str (#27106)
• Index.summary() (#18217)
• .get_ftype_counts (#18243) (#20404)
• .get_dtype_counts #27145
• Index/Series.asobject (#18237) (#18572)
• Index.to_native_types() (make private) (https://github.com/pandas-dev/pandas/pull/36418)
• DataFrame/Series.as_matrix (#18458)
• .clip_upper/.clip_lower (replace by .clip) (#24203)

Potentially

• .ftypes (#18243) (#26744)
• .xs() (#6249)
• .iat/.at
• .take
• .lookup (#35224)
• DataFrame.from_items
• ~Series/DataFrame.add_prefix/add_suffix~ (https://github.com/pandas-dev/pandas/pull/18347)
  • Maybe add suffix / prefix to concat?
• NDFrame.filter

[jimmywan]

Why on earth would you deprecate read_table? That makes no damn sense. The suggested change is to call read_csv to read things that are not comma-separated? This is 100% backwards.

[st-bender]

One could argue why not deprecate read_csv() instead of read_table() since table sounds more flexible.

Edit: I have to agree with @jimmywan here, and if they are basically the same, why not at least keep it as an alias? One could always wrap it, but people would not be confused or avoid updating.