JointGrid.plot_joint(func, **kwargs)
Draw a bivariate plot of <cite>x</cite> and <cite>y</cite>.
参数：func：plotting callable
func
This must take two 1d arrays of data as the first two positional arguments, and it must plot on the “current” axes.
kwargs：key, value mappings
kwargs
Keyword argument are passed to the plotting function.
返回值：self：JointGrid instance
self
Returns <cite>self</cite>.
