python graphviz的使用(画图工具)

参考文章1

参考文章2

一、graphviz安装及配置

graphviz实际上是一个绘图工具,可以根据dot脚本画出树形图等。

 

1、windows安装

  1. 安装graphviz软件:https://graphviz.gitlab.io/_pages/Download/Download_windows.html
  2. 配置环境变量:把bin文件夹的路径加入到环境变量path里
  3. 安装python的graphviz模块:pip install graphviz

 

2、linux centos7安装

  1. yum下载graphviz软件:yum -y install graphviz
  2. 安装python的graphviz模块:pip install graphviz
  3. 测试:which dot

 

二、graphviz的使用

graphviz 有两种图,一种是无向图 graph ,边用 -- 连接,一种是有向图 digraph ,边用 -> 连接

1、初步认识

from graphviz import Digraph

# 实例化一个Digraph对象(有向图),name:生成的图片的图片名,format:生成的图片格式
dot = Digraph(name="MyPicture", comment="the test", format="png")

# 生成图片节点,name:这个节点对象的名称,label:节点名,color:画节点的线的颜色
dot.node(name='a', label='Ming', color='green')
dot.node(name='b', label='Hong', color='yellow')
dot.node(name='c', label='Dong')

# 在节点之间画线,label:线上显示的文本,color:线的颜色
dot.edge('a', 'b', label="ab\na-b", color='red')
# 一次性画多条线,c到b的线,a到c的线
dot.edges(['cb', 'ac'])

# 打印生成的源代码
print(dot.source)

# 画图,filename:图片的名称,若无filename,则使用Digraph对象的name,默认会有gv后缀
# directory:图片保存的路径,默认是在当前路径下保存
dot.view(filename="mypicture", directory="D:\MyTest")

# 跟view一样的用法(render跟view选择一个即可),一般用render生成图片,不使用view=True,view=True用在调试的时候
dot.render(filename='MyPicture', directory="D:\MyTest",view=True)

使用node()和edge()或edges()方法将节点和边添加到图形对象:

  • Digraph():实例化一个图形对象
  • node():方法第一个参数是name,第二个参数是label,即node画节点
  • edges():方法可以一次添加多个边, 每个边用字符串表示, 比如 cb 表示从 c 到 b 的边,即edges画边
  • edge():方法一次添加一个边
  • view():把图形画出来,并自动显示图片(弹出来),一般使用view()进行调试
  • render():把图形画出来,一般使用render保存图片的时候,view=False(不弹出图片)

调试推荐使用 view()

保存图片推荐使用 render(view=False)

 

2、字体乱码

中文的label默认是无法正确显示在图中的, 因为默认的字体并不支持中文, 需要我们为node设置字体。

# 有些字体是需要下载的,默认使用Microsoft YaHei就好

0、字体样式微软雅黑:Microsoft YaHei

1、字体样式华文黑体:STHeiti

2、字体样式华文楷体:STKaiti

3、字体样式华文宋体:STSong

4、字体样式华文仿宋:STFangsong

5、字体样式黑体:SimHei

6、字体样式宋体:SimSun

7、字体样式新宋体:NSimSun

8、字体样式仿宋:FangSong

9、字体样式楷体:KaiTi

10、字体样式仿宋_GB2312:FangSong_GB2312

11、字体样式楷体_GB2312:KaiTi_GB2312

12、字体样式微软正黑体:Microsoft JhengHei

13、字体样式微软雅黑体:Microsoft YaHei

14、字体样式隶书:LiSu

15、字体样式幼圆:YouYuan

16、字体样式华文细黑:STXihei

17、字体样式华文楷体:STKaiti

18、字体样式华文宋体:STSong

19、字体样式华文中宋:STZhongsong

20、字体样式华文仿宋:STFangsong

21、字体样式方正舒体:FZShuTi

22、字体样式方正姚体:FZYaoti

23、字体样式华文彩云:STCaiyun

24、字体样式华文琥珀:STHupo

25、字体样式华文隶书:STLiti

26、字体样式华文行楷:STXingkai

27、字体样式华文新魏:STXinwei
字体样式

 

from graphviz import Digraph

dot = Digraph(name="MyPicture", format="png")
dot.node(name="A", label="老师", fontname="Microsoft YaHei")
dot.node('B', '学生', fontname="Microsoft YaHei")
dot.edge("A", "B", label="教学", fontname="Microsoft YaHei")
dot.render(filename="MyPicture")

 

3、无向图

用法跟有向图一样

from graphviz import Graph

# 无向图
dot = Graph(name="MyPicture", format="png")

dot.node("People")
dot.node("Home")
dot.edge("People", "Home")
dot.view(filename="MyPicture")

 

三、属性(样式)说明

node节点属性如下 

NameDefaultValues
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边框属性

NameDefaultValues
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图属性如下

NameDefaultValues
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参数, 你可以更改图中节点和边的显示样式"""

from graphviz import Digraph

# 可以在实例化对象的时候设置样式
dot = Digraph(name="MyPicture", node_attr={"shape": "plaintext"}, format="png")

# 也可以实例化之后, 设置这些样式
dot.graph_attr['rankdir'] = 'LR'
dot.edge_attr.update(arrowhead='vee', arrowsize='2')

# 然后开始画图
dot.node("Dog")
dot.node("Cat")
dot.edge("Dog", "Cat")

dot.view(filename="MyPicture")

 

四、官网

官方文档

官网

 

posted @ 2019-09-01 13:33  我用python写Bug  阅读(9512)  评论(1编辑  收藏