Matplotlib，多线图绘制轴注释

Question

我有五个点，我想在一张图中使用matplotlib绘制多个x(t)，y(t)和z(t)坐标。我写了这个python代码：

    import matplotlib.pyplot as plt

    fig = plt.figure(4)
    fig.set_facecolor('white')
    yprops = dict(rotation=0,
                 horizontalalignment='right',
                 verticalalignment='center')

    axprops = dict(yticks=[])
    targets = ['centroid_label','centroid_base','centroid_apex','midgland_inferior','midgland_left','midgland_right','midgland_superior']

    count = 0.0
    axlist = []
    for target in targets:
        x,y,z = getXYZMotion_with_compensation(case,target)
        ax = fig.add_axes([0.1, count, 0.8, 0.2], **axprops)
        axlist.append(ax)
        axprops['sharex'] = ax
        axprops['sharey'] = ax
        ax.plot(list_of_times_in_minutes, x)
        ax.plot(list_of_times_in_minutes, y)
        ax.plot(list_of_times_in_minutes, z)
        ax.set_ylabel(target, **yprops)
        count = count + 0.2

    #turn off x ticklabels for all but the lower axes
    for ax in axlist:
      plt.setp(ax.get_xticklabels(), visible=False)

    plt.show()

产生：

但是，我希望所有轴的x轴描述低于最低图形和y轴描述每个子图形从-3到3.我怎样才能实现这一点？