如何阻止matplotlib重新排列栏？

Question

我想从pd.DataFrame绘制条形图。不幸的是，matplotlib不断排列我的小节，显示N = 100，N = 150，N = 50而不是50,100,150

df1 = pd.DataFrame({"N": ["N=50","N=100","N=150","N=50","N=100","N=150","N=50","N=100","N=150"],\
                   "clm2": profit[0:len(profit)],\
                   "User": ["2x2x2","2x2x2","2x2x2","3x3x3","3x3x3","3x3x3","4x4x4","4x4x4","4x4x4"]})



with PdfPages('profit.pdf') as pdf:
    ax1= df1.pivot(index = "User", columns = "N", values = "clm2")
    plt.x_range = FactorRange(factors=df1["N"].tolist())
    ax1.plot.bar(figsize=(7,7),edgecolor = "white",rot=0).set_ylabel("Profits")

    pdf.savefig()