matlab nc文件的读取以及流场的绘制；m_map的应用于绘制地图轮廓以及netcdf 的应用；-read nc documents by matlab,and draw the profile of eastChina by using m_map ,then draw the flow field

绘制东海黑潮海表流速，利用了m_map对图形进行了绘制和修饰(The sea surface velocity of the Kuroshio in the East China Sea was plotted,)

matlab工具包m_map中的一个函数(It is a function in m_map, which is a toolbox of matlab.)