Compute Geary’s C for GeoRaster

        Usage:
        geo.pysal_C(permutations = 1000, rook=True)

        arguments passed to raster_weights() and pysal.Geary
        See help(gr.raster_weights), help(pysal.Geary) for options

def pysal_Geary(self, **kwargs):
        """
        Compute Geary’s C for GeoRaster

        Usage:
        geo.pysal_C(permutations = 1000, rook=True)

        arguments passed to raster_weights() and pysal.Geary
        See help(gr.raster_weights), help(pysal.Geary) for options
        """
        if self.weights is None:
            self.raster_weights(**kwargs)
        rasterf = self.raster.flatten()
        rasterf = rasterf[rasterf.mask==False]
        self.Geary = pysal.Geary(rasterf, self.weights, **kwargs)