docs: def ema_growth(eqdata, **kwargs):
      """
      Growth of exponential moving average.
  
      Parameters
      ----------
      eqdata : DataFrame
      span : int, optional
          Span for exponential moving average. Defaults to 20.
      outputcol : str, optional.
          Column to use for output. Defaults to 'EMA Growth'.
      selection : str, optional
          Column of eqdata on which to calculate ema growth. If
          `eqdata` has only 1 column, `selection` is ignored,
          and ema growth is calculated on that column. Defaults
          to 'Adj Close'.
  
      Returns
      ---------
      out : DataFrame
          Growth of exponential moving average from one day to next
      """
      _growth_outputcol = kwargs.get('outputcol', 'EMA Growth')
      _ema_outputcol = 'EMA'
      kwargs['outputcol'] = _ema_outputcol
      _emadf = ema(eqdata, **kwargs)
      return simple.growth(_emadf, selection=_ema_outputcol, outputcol=_growth_outputcol)