How can I extract orientation of arrows from quiver function?

1 次查看（过去 30 天）

显示更早的评论

annalisa08 2015-3-9

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/182264-how-can-i-extract-orientation-of-arrows-from-quiver-function

评论： Michael Haderlein 2015-3-10

In quiver function where is the information about the arrow orientation?

回答（2 个）

Sean de Wolski 2015-3-10

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/182264-how-can-i-extract-orientation-of-arrows-from-quiver-function#answer_170747

编辑：Sean de Wolski 2015-3-10

在 MATLAB Online 中打开

You'll need to use atan2 to get the orientation from u, v

q = quiver(1,1,1,0.5)
r = atan2(q.VData,q.UData)

r*180/pi to get it into degrees

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

Michael Haderlein 2015-3-9

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/182264-how-can-i-extract-orientation-of-arrows-from-quiver-function#answer_170641

在 MATLAB Online 中打开

quiver actually plots the information.

quiver(x,y,u,v)

means arrows are drawn pointing in (u/v) direction and positioned at (x/y). So, if you have x=0, y=0, u=1, v=1, you get one arrow pointing top right. For multiple arrows, x, y, u and v have multiple values.

5 个评论
显示 3更早的评论隐藏 3更早的评论

annalisa08 2015-3-10

In this way is correct, but my vectors from quiver function start from different origins: x = [-15 0 15;-15 0 15;-15 0 15]; y = [8 8 8; 13 13 13; 18 18 18];u = rand(3,3); v = rand(3,3)

is it possible aligning the vectors in quiver on compass plot?

Thank you very much for the help!

Michael Haderlein 2015-3-10

I don't get it... The origin is lost in the compass plot, but that's an inherent property of the compass plot and has nothing to do with the orientation. Set all x,y to zero and the arrows will align. Set x,y to their correct values (~=0) and they will shift to their correct position but remain their orientation.

请先登录，再进行评论。

请先登录，再回答此问题。