matlab已知两点坐标求角度,matlab三维视角度

链接：http://blog.sina.com.cn/s/blog_994de1530101em5u.html

（1）二维：theta=acosd(dot([x1-x2,y1-y2],隐形的高跟鞋,y3-y4])/(norm([x1-x2,y1-y2])*norm(隐形的高跟鞋,y3-y4])))
（2）三维：theta=acosd(dot([x1-x2,y1-y2,z2-z1],隐形的高跟鞋,y3-y4,z4-z3])/(norm([x1-x2,y1-y2,z2-z1])*norm(隐形的高跟鞋,y3-y4,z4-z3])))