GRAPHVIZ：强制节点位于页面顶部

Question

我正在使用 graphviz，但是我想将节点“This on top”强制到页面顶部，而不是侧面。这是图表：这是代码：g= Digraph('trial', filename='trial.gv')g.attr(compound='true', rankdir="TB" )with g.subgraph() as s:  s.attr(rank='max')  s.node('This on top ')  s.edge('this right under', "Fabrication")with g.subgraph(name='cluster0') as c:    c.node("This")    c.node("that")    c.node("and this on the same level")g.edge("this right under","that", lhead="cluster0" )g.edge("that","This on top ", ltail="cluster0" )g是否有命令可以确保节点按我希望的顶部/底部顺序显示？

Answer 1

第一个问题是，设置强制rank='max'第一个子图中的所有内容达到最高等级，即最低等级。您可能打算设置rank='min'将子图中的项目置于最高等级，但这仍然无法创建您想要的排列。

相反，您可以通过在创建边缘时进行设置来使用不可见边缘style = 'invis'，以强制“此在顶部”位于“此在右下”之前。

from graphviz import Digraph

g= Digraph('trial', filename='trial.gv')

g.attr(compound='true', rankdir="TB" )

with g.subgraph() as s:

  # s.attr(rank='min') # you don't need this line

  s.node('This on top ')

  s.edge('This on top ', 'this right under', style='invis') # add this invisible edge

  s.edge('this right under', "Fabrication")

with g.subgraph(name='cluster0') as c:

    c.node("This")

    c.node("that")

    c.node("and this on the same level")

g.edge("this right under", "that", lhead="cluster0" )

g.edge("that", "This on top ", ltail="cluster0", constraint="false" )

g

其产生：