一、graphviz安裝及配置
graphviz實際上是一個繪圖工具，可以根據dot腳本畫出樹形圖等。
1、windows安裝
- 安裝graphviz軟件：https://graphviz.gitlab.io/_pages/Download/Download_windows.html
- 配置環境變量：把bin文件夾的路徑加入到環境變量path里
- 安裝python的graphviz模塊：pip install graphviz
2、linux centos7安裝
- yum下載graphviz軟件：yum -y install graphviz
- 安裝python的graphviz模塊：pip install graphviz
- 測試：which dot
二、graphviz的使用
graphviz 有兩種圖，一種是無向圖 graph ，邊用 -- 連接，一種是有向圖 digraph ，邊用 -> 連接
1、初步認識
from graphviz import Digraph # 實例化一個Digraph對象(有向圖)，name:生成的圖片的圖片名，format:生成的圖片格式 dot = Digraph(name="MyPicture", comment="the test", format="png") # 生成圖片節點，name：這個節點對象的名稱，label:節點名,color：畫節點的線的顏色 dot.node(name='a', label='Ming', color='green') dot.node(name='b', label='Hong', color='yellow') dot.node(name='c', label='Dong') # 在節點之間畫線，label：線上顯示的文本,color:線的顏色 dot.edge('a', 'b', label="ab\na-b", color='red') # 一次性畫多條線，c到b的線，a到c的線 dot.edges(['cb', 'ac']) # 打印生成的源代碼 print(dot.source) # 畫圖，filename:圖片的名稱，若無filename，則使用Digraph對象的name，默認會有gv后綴 # directory:圖片保存的路徑，默認是在當前路徑下保存 dot.view(filename="mypicture", directory="D:\MyTest") # 跟view一樣的用法(render跟view選擇一個即可)，一般用render生成圖片，不使用view=True,view=True用在調試的時候 dot.render(filename='MyPicture', directory="D:\MyTest",view=True)
使用node()和edge()或edges()方法將節點和邊添加到圖形對象：
- Digraph()：實例化一個圖形對象
- node()：方法第一個參數是name，第二個參數是label，即node畫節點
edges()：方法可以一次添加多個邊, 每個邊用字符串表示, 比如cb表示從 c 到 b 的邊，即edges畫邊edge()：方法一次添加一個邊- view()：把圖形畫出來，並自動顯示圖片(彈出來),一般使用view()進行調試
- render()：把圖形畫出來，一般使用render保存圖片的時候，view=False(不彈出圖片)
調試推薦使用 view()
保存圖片推薦使用 render(view=False)
2、字體亂碼
中文的label默認是無法正確顯示在圖中的, 因為默認的字體並不支持中文, 需要我們為node設置字體。
# 有些字體是需要下載的，默認使用Microsoft YaHei就好 0、字體樣式微軟雅黑：Microsoft YaHei 1、字體樣式華文黑體：STHeiti 2、字體樣式華文楷體：STKaiti 3、字體樣式華文宋體：STSong 4、字體樣式華文仿宋：STFangsong 5、字體樣式黑體：SimHei 6、字體樣式宋體：SimSun 7、字體樣式新宋體：NSimSun 8、字體樣式仿宋：FangSong 9、字體樣式楷體：KaiTi 10、字體樣式仿宋_GB2312：FangSong_GB2312 11、字體樣式楷體_GB2312：KaiTi_GB2312 12、字體樣式微軟正黑體：Microsoft JhengHei 13、字體樣式微軟雅黑體：Microsoft YaHei 14、字體樣式隸書：LiSu 15、字體樣式幼圓：YouYuan 16、字體樣式華文細黑：STXihei 17、字體樣式華文楷體：STKaiti 18、字體樣式華文宋體：STSong 19、字體樣式華文中宋：STZhongsong 20、字體樣式華文仿宋：STFangsong 21、字體樣式方正舒體：FZShuTi 22、字體樣式方正姚體：FZYaoti 23、字體樣式華文彩雲：STCaiyun 24、字體樣式華文琥珀：STHupo 25、字體樣式華文隸書：STLiti 26、字體樣式華文行楷：STXingkai 27、字體樣式華文新魏：STXinwei
from graphviz import Digraph dot = Digraph(name="MyPicture", format="png") dot.node(name="A", label="老師", fontname="Microsoft YaHei") dot.node('B', '學生', fontname="Microsoft YaHei") dot.edge("A", "B", label="教學", fontname="Microsoft YaHei") dot.render(filename="MyPicture")
3、無向圖
用法跟有向圖一樣
from graphviz import Graph # 無向圖 dot = Graph(name="MyPicture", format="png") dot.node("People") dot.node("Home") dot.edge("People", "Home") dot.view(filename="MyPicture")
三、屬性(樣式)說明
node節點屬性如下
| Name | Default | Values |
|---|---|---|
| color | black | node shape color |
| comment | any string (format-dependent) | |
| distortion | 0.0 | node distortion for shape=polygon |
| fillcolor | lightgrey/black | node fill color |
| fixedsize | false | label text has no affect on node size |
| fontcolor | black | type face color |
| fontname | Times-Roman | font family |
| fontsize | 14 | point size of label |
| group | name of node’s group | |
| height | .5 | height in inches |
| label | node name | any string |
| layer | overlay range | all, id or id:id |
| orientation | 0.0 | node rotation angle |
| peripheries | shape-dependent | number of node boundaries |
| regular | false | force polygon to be regular |
| shape | ellipse | node shape; see Section 2.1 and Appendix E |
| shapefile | external EPSF or SVG custom shape file | |
| sides | 4 | number of sides for shape=polygon |
| skew | 0.0 | skewing of node for shape=polygon |
| style | graphics options, e.g. bold, dotted, filled; cf. Section 2.3 | |
| URL | URL associated with node (format-dependent) | |
| width | .75 | width in inches |
| z | 0.0 | z coordinate for VRML output |
edge邊框屬性
| Name | Default | Values |
|---|---|---|
| arrowhead | normal | style of arrowhead at head end |
| arrowsize | 1.0 | scaling factor for arrowheads |
| arrowtail | normal | style of arrowhead at tail end |
| color | black | edge stroke color |
| comment | any string (format-dependent) | |
| constraint | true | use edge to affect node ranking |
| decorate | if set, draws a line connecting labels with their edges | |
| dir | forward | forward, back, both, or none |
| fontcolor | black | type face color |
| fontname | Times-Roman | font family |
| fontsize | 14 | point size of label |
| headlabel | label placed near head of edge | |
| headport | n,ne,e,se,s,sw,w,nw | |
| headURL | URL attached to head label if output format is ismap | |
| label | edge label | |
| labelangle | -25.0 | angle in degrees which head or tail label is rotated off edge |
| labeldistance | 1.0 | scaling factor for distance of head or tail label from node |
| labelfloat | false | lessen constraints on edge label placement |
| labelfontcolor | black | type face color for head and tail labels |
| labelfontname | Times-Roman | font family for head and tail labels |
| labelfontsize | 14 | point size for head and tail labels |
| layer | overlay range | all, id or id:id |
| lhead | name of cluster to use as head of edge | |
| ltail | name of cluster to use as tail of edge | |
| minlen | 1 | minimum rank distance between head and tail |
| samehead | tag for head node; edge heads with the same tag are | |
| sametail | merged onto the same port | |
| style | tag for tail node; edge tails with the same tag are merged onto the same port | |
| taillabel | graphics options, e.g. bold, dotted, filled; cf. Section 2.3 | |
| tailport | label placed near tail of edge n,ne,e,se,s,sw,w,nw | |
| tailURL | URL attached to tail label if output format is ismap | |
| weight | 1 | integer cost of stretching an edge |
Digraph圖屬性如下
| Name | Default | Values |
|---|---|---|
| bgcolor | background color for drawing, plus initial fill color | |
| center | false | center drawing on page |
| clusterrank | local | may be global or none |
| color | black | for clusters, outline color, and fill color if fillcolor not defined |
| comment | any string (format-dependent) | |
| compound | false | allow edges between clusters |
| concentrate | false | enables edge concentrators |
| fillcolor | black | cluster fill color |
| fontcolor | black | type face color |
| fontname | Times-Roman | font family |
| fontpath | list of directories to search for fonts | |
| fontsize | 14 | point size of label |
| label | any string | |
| labeljust | centered | ”l” and ”r” for left- and right-justified cluster labels, respectively |
| labelloc | top | ”t” and ”b” for top- and bottom-justified cluster labels, respectively |
| layers | id:id:id… | |
| margin | .5 | margin included in page, inches |
| mclimit | 1.0 | scale factor for mincross iterations |
| nodesep | .25 | separation between nodes, in inches. |
| nslimit | if set to f, bounds network simplex iterations by (f)(number of nodes) when setting x-coordinates | |
| nslimit1 | if set to f, bounds network simplex iterations by (f)(number of nodes) when ranking nodes | |
| ordering | if out out edge order is preserved | |
| orientation | portrait | if rotate is not used and the value is landscape, use landscape orientation |
| page | unit of pagination, e.g. “8.5,11” | |
| pagedir | BL | traversal order of pages |
| quantum | if quantum ¿ 0.0, node label dimensions will be rounded to integral multiples of quantum | |
| rank | same, min, max, source or sink | |
| rankdir | TB | LR (left to right) or TB (top to bottom) |
| ranksep | .75 | separation between ranks, in inches. |
| ratio | approximate aspect ratio desired, fill or auto | |
| remincross | if true and there are multiple clusters, re-run crossing minimization | |
| rotate | If 90, set orientation to landscape | |
| samplepoints | 8 | number of points used to represent ellipses and circles on output (cf. Appendix C |
| searchsize | 30 | maximum edges with negative cut values to check when looking for a minimum one during network simplex |
| size | maximum drawing size, in inches | |
| style | graphics options, e.g. filled for clusters | |
| URL | URL associated with graph (format-dependent) |
例子
"""使用graph_attr, node_attr, edge_attr參數, 你可以更改圖中節點和邊的顯示樣式""" from graphviz import Digraph # 可以在實例化對象的時候設置樣式 dot = Digraph(name="MyPicture", node_attr={"shape": "plaintext"}, format="png") # 也可以實例化之后, 設置這些樣式 dot.graph_attr['rankdir'] = 'LR' dot.edge_attr.update(arrowhead='vee', arrowsize='2') # 然后開始畫圖 dot.node("Dog") dot.node("Cat") dot.edge("Dog", "Cat") dot.view(filename="MyPicture")
四、官網