def plot_correlation(self, freq=None, title=None,
                         figsize=(12, 6), **kwargs):
        """
        Utility function to plot correlations.

        Args:
            * freq (str): Pandas data frequency alias string
            * title (str): Plot title
            * figsize (tuple (x,y)): figure size
            * kwargs: passed to Pandas' plot_corr_heatmap function

        """
        if title is None:
            title = self._get_default_plot_title(
                freq, 'Return Correlation Matrix')

        rets = self._get_series(freq).to_returns().dropna()
        return rets.plot_corr_heatmap(title=title, figsize=figsize, **kwargs)
Utility function to plot correlations.

        Args:
            * freq (str): Pandas data frequency alias string
            * title (str): Plot title
            * figsize (tuple (x,y)): figure size
            * kwargs: passed to Pandas' plot_corr_heatmap function