解决绘制3D散点图报错：TypeError: gca() got an unexpected keyword argument ‘projection’

 问题：使用matplotlib绘制3d散点图时报错ax = fig.gca(projection = '3d')
TypeError: gca() got an unexpected keyword argument 'projection'

解决：改成如下代码即可运行

ax = fig.add_subplot(projection = '3d')