docs: def plotConnectivity(ax):
      '''make an imshow of the intranetwork connectivity'''
      im = ax.pcolor(params.C_YX, cmap='hot')
      ax.axis(ax.axis('tight'))
      ax.invert_yaxis()
      ax.xaxis.set_ticks_position('top')
      ax.set_xticks(np.arange(9)+0.5)
      ax.set_yticks(np.arange(8)+0.5)
      ax.set_xticklabels(params.X, rotation=270)
      ax.set_yticklabels(params.Y, )
      #ax.set_ylabel(r'to ($Y$)', ha='center')
      #ax.set_xlabel(r'from ($X$)', va='center')
      ax.xaxis.set_label_position('top')
  
      rect = np.array(ax.get_position().bounds)
      rect[0] += rect[2] + 0.01
      rect[2] = 0.01
      fig = plt.gcf()
      cax = fig.add_axes(rect)
  
      cbar = plt.colorbar(im, cax=cax)
      cbar.set_label('connectivity', ha='center')