TreeRules

[Experimental]

✖

TreeRules[tree]

returns the rules associated with the Tree object tree.

Details

TreeRules returns the rules associated with a tree expression.
The inverse operation of TreeRules is performed by RulesTree.
If tree has a list of children, then TreeRules[tree] gives data{rule₁,rule₂,…}, where data is the data in tree and rule_i are the rules associated with its children.
TreeRules[Tree[data,<|key₁tree₁,key₂tree₂,…|>]] gives data<|key₁TreeRules[tree₁],key₂TreeRules[tree₂],…|>.
TreeRules[Tree[data,None]] for data of the form …{…}, …<|…|> or …None gives dataNone rather than data. »

Examples

open allclose all

Basic Examples (3)Summary of the most common use cases

Get the rules associated with a tree with three leaves:

In[2]:=2

✖

https://wolfram.com/xid/0cg4dlx0i-e6vv2q

Out[2]=2

Get the rules for a tree with several levels:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-wrio5b

Out[1]=1

Get the rules for a tree with named edges:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-svu93p

Out[1]=1

Scope (4)Survey of the scope of standard use cases

Use TreeRules on a leaf with no child:

In[2]:=2

✖

https://wolfram.com/xid/0cg4dlx0i-zphtoo

Out[2]=2

Use TreeRules on an inner node with no children:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-sswytq

Out[1]=1

In[2]:=2

✖

https://wolfram.com/xid/0cg4dlx0i-qiz7ys

Out[2]=2

Use TreeRules on a tree with a list of children:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-454bw2

Out[1]=1

Use TreeRules on a tree with an association of children:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-k29xlg

Out[1]=1

Properties & Relations (2)Properties of the function, and connections to other functions

RulesTree constructs a tree associated with the given rules:

In[3]:=3

✖

https://wolfram.com/xid/0cg4dlx0i-x0uoyc

Out[3]=3

Use TreeRules on the result to recover the original rules:

In[4]:=4

✖

https://wolfram.com/xid/0cg4dlx0i-7cxq5i

Out[4]=4

TreeRules[tree] is generally equivalent to TreeFold[{Rule,Identity},tree]:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-6gne4o

Out[1]=1

In[2]:=2

✖

https://wolfram.com/xid/0cg4dlx0i-eo4gil

Out[2]=2

Possible Issues (1)Common pitfalls and unexpected behavior

TreeRules[Tree[data,None]] generally gives data:

In[1]:=1

✖

https://wolfram.com/xid/0cg4dlx0i-84e3vt

Out[1]=1

However, TreeRules[Tree[expr{…},None]] gives (expr{…})None instead:

In[2]:=2

✖

https://wolfram.com/xid/0cg4dlx0i-y1qdhp

Out[2]=2

Top