python matplotlib.pyplot不渲染时间序列图

Question

ax.plot() doesn't render the time series plot, while pandas.plot() and plt.scatter() works. But because I need to reform my axis, I need to use ax.plot() .

My data:

When I try to plot it: ax=df_cuba['ORD'].plot()

It works perfectly:

But when I try to use : plt.plot(x=df_cuba.index,y=df_cuba['ORD'])

It shows nothing:

It also works for scatterplot .

I couldn't find any posts about this. I suspect the py.plot is trying a different way to plot time series data.

Answer 1

plot does not have named x and y arguments. So suppose you have xdata and ydata you want to plot, you cannot use plt.plot(x=xdata, y=ydata) , but instead need

plt.plot(xdata, ydata)

For scatter this is different, here you can use both

plt.scatter(xdata, ydata)
plt.scatter(x=xdata, y=ydata)

Answer 2

我发现了真正的原因： plt.plot只能绘制数值数据，因此，如果要使用np.datetime64或pd.datetime格式绘制时间序列数据，则需要使用以下命令：

plt.plot_date(date, y)