如何用箭头连接 3D 散点图中的两个点？答案

【问题标题】：How can I connect two points in 3D scatter plot with arrow?如何用箭头连接 3D 散点图中的两个点？
【发布时间】：2016-07-05 02:09:28
【问题描述】：

我正在尝试用箭头连接 3D 散点图中的两个点。我尝试使用带有以下代码的quiver

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

fig = plt.figure(figsize=(20, 15))
ax = fig.add_subplot(111, projection='3d')

xs1 = [40,50,34]
ys1 = [30,30,30]
zs1 = [98,46,63]

ax.scatter(xs1, ys1, zs1, s=100, c='g', marker='o')

ax.text(xs1[0], ys1[0], zs1[0], '(%s,%s,%s)' % (str(xs1[0]), str(ys1[0]), str(zs1[0])), size=30, zorder=5, color='k')
ax.text(xs1[1], ys1[1], zs1[1], '(%s,%s,%s)' % (str(xs1[1]), str(ys1[1]), str(zs1[1])), size=30, zorder=5, color='k')
ax.text(xs1[2], ys1[2], zs1[2], '(%s,%s,%s)' % (str(xs1[2]), str(ys1[2]), str(zs1[2])), size=30, zorder=5, color='k')


ax.quiver(xs1[0], ys1[0], zs1[0], (xs1[0]-xs1[2]), (ys1[0]-ys1[2]), (zs1[0]-zs1[2]), length=30)


ax.set_xlabel('X', fontsize=30, labelpad=20)
ax.set_ylabel('Y', fontsize=30, labelpad=20)
ax.set_zlabel('Z', fontsize=30, labelpad=20)

plt.show()
fig.canvas.draw()
fig.canvas.flush_events()

看起来像这样

我能够连接这两个点的唯一方法是增加quiver 的length，但如果length 超出了要求，它只会通过另一点。

有没有更好的方法在不调整长度的情况下连接它们？

【问题讨论】：

标签： python matplotlib mplot3d

【解决方案1】：

基于FancyArrow构造自己的类以在3d维度上绘制：

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
from mpl_toolkits.mplot3d import proj3d
from matplotlib.patches import FancyArrowPatch

class Arrow3D(FancyArrowPatch):
    def __init__(self, xs, ys, zs, *args, **kwargs):
        FancyArrowPatch.__init__(self, (0,0), (0,0), *args, **kwargs)
        self._verts3d = xs, ys, zs

    def draw(self, renderer):
        xs3d, ys3d, zs3d = self._verts3d
        xs, ys, zs = proj3d.proj_transform(xs3d, ys3d, zs3d, renderer.M)
        self.set_positions((xs[0],ys[0]),(xs[1],ys[1]))
        FancyArrowPatch.draw(self, renderer)

fig = plt.figure(figsize=(20, 15))
ax = fig.add_subplot(111, projection='3d')

xs1 = [40,50,34]
ys1 = [30,30,30]
zs1 = [98,46,63]

ax.scatter(xs1, ys1, zs1, s=100, c='g', marker='o')

ax.text(xs1[0], ys1[0], zs1[0], '(%s,%s,%s)' % (str(xs1[0]), str(ys1[0]), str(zs1[0])), size=30, zorder=5, color='k')
ax.text(xs1[1], ys1[1], zs1[1], '(%s,%s,%s)' % (str(xs1[1]), str(ys1[1]), str(zs1[1])), size=30, zorder=5, color='k')
ax.text(xs1[2], ys1[2], zs1[2], '(%s,%s,%s)' % (str(xs1[2]), str(ys1[2]), str(zs1[2])), size=30, zorder=5, color='k')

arw = Arrow3D([xs1[0],xs1[2]],[ys1[0],ys1[2]],[zs1[0],zs1[2]], arrowstyle="->", color="purple", lw = 3, mutation_scale=25)
ax.add_artist(arw)

ax.set_xlabel('X', fontsize=30, labelpad=20)
ax.set_ylabel('Y', fontsize=30, labelpad=20)
ax.set_zlabel('Z', fontsize=30, labelpad=20)

plt.show()

以上代码基于此answer阅读了解更多详情。

【讨论】：