Plotly：如何使用 plotly.graph_objects 将两个 3D 图放在同一个图上？

Posted 2023-02-18

【中文标题】Plotly：如何使用 plotly.graph_objects 将两个 3D 图放在同一个图上？

【英文标题】：Plotly: How to put two 3D graphs on the same plot with plotly.graph_objects?

【发布时间】：2021-02-16 23:50:03

【问题描述】：

在下面的代码中，我用plotly.graph_objects 绘制了 2 个 3D 图形。我无法将它们放在一起。

import plotly.graph_objects as go
import numpy as np

pts = np.loadtxt(np.DataSource().open('https://raw.githubusercontent.com/plotly/datasets/master/mesh_dataset.txt'))
x, y, z = pts.T

### First graph
fig = go.Figure(data=[go.Mesh3d(x=x, y=y, z=z,
                   alphahull=5,
                   opacity=0.4,
                   color='cyan')])
fig.show()
#######

x = [0, 1, 0]
y = [0, 2, 3]
tvects = [x,y]
orig = [0,0,0]
df=[]
coords = [[orig, np.sum([orig, v],axis=0)] for v in tvects]

for i,c in enumerate(coords):
    X1, Y1, Z1 = zip(c[0])
    X2, Y2, Z2 = zip(c[1])
    vector = go.Scatter3d(x = [X1[0],X2[0]],
                          y = [Y1[0],Y2[0]],
                          z = [Z1[0],Z2[0]],
                          marker = dict(size = [0,5],
                                        color = ['blue'],
                                        line=dict(width=5,
                                                  color='DarkSlateGrey')),
                          name = 'Vector'+str(i+1))
    data.append(vector)

### Second graph
fig = go.Figure(data=data)
fig.show()
########

您能否详细说明如何做到这一点，以及如何在第二张图中使用带头的箭头而不是线？

【参考方案1】：

如果您想在您的第一个 fig 定义的基础上构建，只需在您第一次调用 go.Figure() 后添加以下内容

data = fig._data

data 现在是一个列表，它将在您已经存在的代码的其余部分中附加新元素：

for i,c in enumerate(coords):
    X1, Y1, Z1 = zip(c[0])
    X2, Y2, Z2 = zip(c[1])
    vector = go.Scatter3d(<see details in snippet below>)
    data.append(vector)

结果：

关于箭头，您可以通过go.Scatter3D 直接获得的唯一选项是：

['circle', 'circle-open', 'square', 'square-open','diamond', 'diamond-open', 'cross', 'x']

我希望其中一个选项能满足您的需求。您可以指定其中一个：

marker = dict(size = [15,15],
            color = ['blue'],
            symbol = 'diamond',
            line=dict(width=500,
                      #color='red'
                     )),

完整代码：

import plotly.graph_objects as go
import numpy as np

pts = np.loadtxt(np.DataSource().open('https://raw.githubusercontent.com/plotly/datasets/master/mesh_dataset.txt'))
x, y, z = pts.T

### First graph
fig = go.Figure(data=[go.Mesh3d(x=x, y=y, z=z,
                   alphahull=5,
                   opacity=0.4,
                   color='cyan')])
#fig.show()
#######

data = fig._data

x = [0, 1, 0]
y = [0, 2, 3]
tvects = [x,y]
orig = [0,0,0]
df=[]
coords = [[orig, np.sum([orig, v],axis=0)] for v in tvects]

# ['circle', 'circle-open', 'square', 'square-open','diamond', 'diamond-open', 'cross', 'x']

for i,c in enumerate(coords):
    X1, Y1, Z1 = zip(c[0])
    X2, Y2, Z2 = zip(c[1])
    vector = go.Scatter3d(x = [X1[0],X2[0]],
                          y = [Y1[0],Y2[0]],
                          z = [Z1[0],Z2[0]],
                          marker = dict(size = [15,15],
                                        color = ['blue'],
                                        symbol = 'diamond',
                                        line=dict(width=500,
                                                  #color='red'
                                                 )),
                          name = 'Vector'+str(i+1))
    data.append(vector)

### Second graph
fig = go.Figure(data=data)
fig.show()
########

【讨论】：

请问如何为每个向量设置一个箭头？

@LAD 还没有找到实现箭头的方法，但至少你还有其他选择。看看我上次的编辑。