加载输入图的不同方法#

我们建议使用GML图格式来加载图。你也可以使用DOT格式，但这需要额外的依赖（pydot或pygraphviz）。

DoWhy 支持将图作为字符串加载，或作为文件加载（扩展名为 'gml' 或 'dot'）。

下面是一个展示加载同一图形的不同方式的示例。

[1]:

import os, sys
import random
sys.path.append(os.path.abspath("../../../"))

[2]:

import numpy as np
import pandas as pd

import dowhy
from dowhy import CausalModel
from IPython.display import Image, display

I. 生成虚拟数据#

我们为三个变量生成了一些虚拟数据：X、Y 和 Z。

[3]:

z=[i for i in range(10)]
random.shuffle(z)
df = pd.DataFrame(data = {'Z': z, 'X': range(0,10), 'Y': range(0,100,10)})
df

[3]:
Z X Y
0 3 0 0
1 7 1 10
2 8 2 20
3 4 3 30
4 0 4 40
5 9 5 50
6 1 6 60
7 6 7 70
8 5 8 80
9 2 9 90

II. 加载GML或DOT图形#

GML格式#

[4]:

# With GML string
model=CausalModel(
        data = df,
        treatment='X',
        outcome='Y',
        graph="""graph[directed 1 node[id "Z" label "Z"]
                    node[id "X" label "X"]
                    node[id "Y" label "Y"]
                    edge[source "Z" target "X"]
                    edge[source "Z" target "Y"]
                    edge[source "X" target "Y"]]"""

        )
model.view_model()


display(Image(filename="causal_model.png"))
../_images/example_notebooks_load_graph_example_6_0.png
../_images/example_notebooks_load_graph_example_6_1.png 
[5]:

# With GML file
model=CausalModel(
        data = df,
        treatment='X',
        outcome='Y',
        graph="../example_graphs/simple_graph_example.gml"
        )
model.view_model()


display(Image(filename="causal_model.png"))
../_images/example_notebooks_load_graph_example_7_0.png
../_images/example_notebooks_load_graph_example_7_1.png

DOT格式#

[6]:

# With DOT string
model=CausalModel(
        data = df,
        treatment='X',
        outcome='Y',
        graph="digraph {Z -> X;Z -> Y;X -> Y;}"
        )
model.view_model()

from IPython.display import Image, display
display(Image(filename="causal_model.png"))
../_images/example_notebooks_load_graph_example_9_0.png
../_images/example_notebooks_load_graph_example_9_1.png 
[7]:

# With DOT file
model=CausalModel(
        data = df,
        treatment='X',
        outcome='Y',
        graph="../example_graphs/simple_graph_example.dot"
        )
model.view_model()


display(Image(filename="causal_model.png"))
../_images/example_notebooks_load_graph_example_10_0.png
../_images/example_notebooks_load_graph_example_10_1.png