How to overplot a line on a scatter plot in python?

Question

I have two vectors of data and I\'ve put them into matplotlib.scatter(). Now I\'d like to over plot a linear fit to these data. How would I do this? I\'ve tried

Answer 1

plt.plot(X_plot, X_plot*results.params[0] + results.params[1])

versus

plt.plot(X_plot, X_plot*results.params[1] + results.params[0])