I have dealt with all the Nan values in the features dataframe, then why I am still getting this error? 

sns.heatmap(features, annot=True, annot_kws={"size": 7})
sns.plt.show()

TypeError                                 Traceback (most recent call last)
    <ipython-input-11-534a699b432d> in <module>()
    ----> 1 sns.heatmap(features, annot=True, annot_kws={"size": 7})
          2 sns.plt.show()

    c:\users\jetjo\appdata\local\programs\python\python36\lib\site-packages\seaborn\matrix.py in heatmap(data, vmin, vmax, cmap, center, robust, annot, fmt, annot_kws, linewidths, linecolor, cbar, cbar_kws, cbar_ax, square, xticklabels, yticklabels, mask, ax, **kwargs)
        515     plotter = _HeatMapper(data, vmin, vmax, cmap, center, robust, annot, fmt,
        516                           annot_kws, cbar, cbar_kws, xticklabels,
    --> 517                           yticklabels, mask)
        518 
        519     # Add the pcolormesh kwargs here

    c:\users\jetjo\appdata\local\programs\python\python36\lib\site-packages\seaborn\matrix.py in __init__(self, data, vmin, vmax, cmap, center, robust, annot, fmt, annot_kws, cbar, cbar_kws, xticklabels, yticklabels, mask)
        166         # Determine good default values for the colormapping
        167         self._determine_cmap_params(plot_data, vmin, vmax,
    --> 168                                     cmap, center, robust)
        169 
        170         # Sort out the annotations

    c:\users\jetjo\appdata\local\programs\python\python36\lib\site-packages\seaborn\matrix.py in _determine_cmap_params(self, plot_data, vmin, vmax, cmap, center, robust)
        203                                cmap, center, robust):
        204         """Use some heuristics to set good defaults for colorbar and range."""
    --> 205         calc_data = plot_data.data[~np.isnan(plot_data.data)]
        206         if vmin is None:
        207             vmin = np.percentile(calc_data, 2) if robust else calc_data.min()

    TypeError: ufunc 'isnan' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''