Pyplot趋势线不会显示在散点图上，而是在它的右边？

Question

我编写了代码以创建散点图并获得线性趋势线方程，但是pyplot不会将趋势线直接放在散点图上。

这里是代码（很麻烦！）：

for acc in accdict:
            cc = 'b'
            zz = 50
            if str(accdict\[acc\]\[0\]) in str(alt):
                cc = 'r'
                for item in accdict\[acc\]\[1\]:
                    altx.append(float(item))
                for item in accdict\[acc\]\[2\]:
                    alty.append(float(item))
                if altcount < refcount:
                    zz = 100
                else:
                    zz = 0
            else:
                for item in accdict\[acc\]\[1\]:
                    refx.append(float(item))
                for item in accdict\[acc\]\[2\]:
                    refy.append(float(item))
            plt.scatter(accdict\[acc\]\[1\], accdict\[acc\]\[2\], color=cc, zorder=zz)
        #plt.plot(np.unique(altx), np.poly1d(np.polyfit(altx, alty, 1))(np.unique(altx)), color='r',zorder=zz)
        (m,b) = np.polyfit(altx ,alty ,1)
        p = np.poly1d((m,b))
        plt.plot(altx, p(altx), color='r', zorder=z)
        yp = np.polyval(\[m,b\], altx)
        alteq = phen + ' = ' + str(round(m, 4)) + 'x' ' + ' + str(round(b, 4))
        plt.plot(np.unique(refx), np.poly1d(np.polyfit(refx, refy, 1))(np.unique(refx)), color='b', zorder=zz)
        (m,b) = np.polyfit(refx ,refy ,1)
        yp = np.polyval(\[m,b\], refx)
        refeq = phen + ' = ' + str(round(m, 4)) + 'x' ' + ' + str(round(b, 4))
        plt.annotate('          ' + alteq, xy=(0.5, 0), xytext=(0, 10), xycoords=('axes fraction', 'figure fraction'), textcoords='offset points', size=8, ha='left', va='bottom', color='r')
        plt.annotate(refeq + '          ',xy=(0.5, 0), xytext=(0, 10), xycoords=('axes fraction', 'figure fraction'), textcoords='offset points', size=8, ha='right', va='bottom', color='b')
        plt.xlabel('Days')
        plt.ylabel(phen)
        red_patch = mpatches.Patch(color='red', label='Alt')
        blue_patch = mpatches.Patch(color='blue', label='Ref')
        plt.legend(handles=\[red_patch,blue_patch\],loc='best')
        plt.title('Position:'+sheetname+' '+phen+' Over Time')
        newpath = '/Users/elijahsaltzman/'+filename\[:-4\]+'-scatter/'+sheetname
        if not os.path.exists(newpath):
            os.makedirs(newpath)
        plt.savefig(newpath + '/' + phen + '.png')
        plt.close()