def __init__(self, hic_matrix, regions=None, colormap='RdBu', norm="log",
                 vmin=None, vmax=None, show_colorbar=True, blend_masked=False):
        if regions is None:
            for i in range(hic_matrix.shape[0]):
                regions.append(GenomicRegion(chromosome='', start=i, end=i))
        self.regions = regions
        self.hic_matrix = hic_matrix

        self.colormap = copy.copy(mpl.cm.get_cmap(colormap))
        if blend_masked:
            self.colormap.set_bad(self.colormap(0))
        self._vmin = vmin
        self._vmax = vmax
        self.norm = prepare_normalization(norm=norm, vmin=vmin, vmax=vmax)
        self.colorbar = None
        self.slider = None
        self.show_colorbar = show_colorbar