Panel pct_change bug

[shura-v]

  File "z:\code\m.py", line 420, in get_panel
    self.source_panel.pct_change()
  File "c:\anaconda\lib\site-packages\pandas\core\generic.py", line 3418, in pct_change
    rs = data / data.shift(periods=periods, freq=freq, **kwds) - 1
TypeError: shift() got an unexpected keyword argument 'periods'

pandas.version.version
Out[5]: '0.13.1'

[TomAugspurger]

Thanks for the report. This is a bug.

DataFrame.shift's args are periods=1, freq=None, axis=0, **kwds and Panel's are lags, freq=None, axis='major'.

@jreback I can fix this in common.pct_change by passing periods as a positional arg instead of kwarg. Should I also put a deprecation warning on Panel.shift about changing the lag keyword to periods to be consistent with DataFrame?

[jreback]

hmm this in master?

ok tom sounds good (depr on change ok)
put the ref in the master depr issue (for 0.16)

[TomAugspurger]

Actually not that simple. This should be double, but I'll have to adjust the implementation a bit.