Quiver matplotlib：具有相同尺寸的箭头

Question

I'm trying to do a plot with quiver but I would like the arrows to all have the same size.

I use the following input :

q = ax0.quiver(x, y, dx, dy, units='xy' ,scale=1) 

But even if add options like norm = 'true' or Normalize = 'true' the arrows are not normalized

Any one knows how to do this ? Thank you

Answer 1

Not sure if there is a way to do this by explicitly providing a kwarg to plt.quiver, but a quick work around would be like this:

original plot

x = np.arange(10)
y = np.arange(10)
xx, yy = np.meshgrid(x,y)
u = np.random.uniform(low=-1, high=1, size=(9,9))
v = np.random.uniform(low=-1, high=1, size=(9,9))
plt.quiver(xx, yy, u, v)

normalized plot

r = np.power(np.add(np.power(u,2), np.power(v,2)),0.5) #could do (u**2+v**2)**0.5, other ways...
plt.quiver(xx, yy, u/r, v/r)

this just normalizes the u and v components of the vector by the magnitude of the vector, thereby maintaining the proper direction, but scaling down the magnitude of each arrow to 1

Answer 2

没有足够的声誉来评论@Derek 的帖子，但是可以通过说明代码的目的来更清楚地写出这一点 -将向量除以幅度以到达方向。