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 NestTreeInteractive (1.0.0) current version: 1.0.2 »

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Interactively construct a tree

Contributed by: Ian Ford

ResourceFunction["NestTreeInteractive"][f,expr0]

gives an interactive tree with initial data expr0, where clicking a leaf with data expr adds new children defined by f[expr].

ResourceFunction["NestTreeInteractive"][f,expr0,h]

additionally applies h to the data of the clicked node.

Details

ResourceFunction["NestTreeInteractive"] is an interactive version of NestTree.
ResourceFunction["NestTreeInteractive"] grows Tree objects, adding successively deeper levels of children to the leaves using an operation f.
ResourceFunction["NestTreeInteractive"] is useful for constructing a tree from an expression.
Whenever a leaf Tree[expr,None] is clicked, it is replaced by Tree[expr,{Tree[expr1,None],…}], where f[expr] gives {expr1,expr2,…}.
If f returns None or {}, no futher levels can be added to that leaf.
In NestTree[f,expr,h], clicking a leaf Tree[expr,None] replaces it with Tree[h[expr],…].
f[expr] should give {expr1,expr2,…} or None.
If f does not return {…} or None, ResourceFunction["NestTreeInteractive"][f,expr,…] is equivalent to ResourceFunction["NestTreeInteractive"][List@*f,expr,…].

Examples

Basic Examples (2) 

Interactively build a tree from an expression:

In[1]:=
ResourceFunction["NestTreeInteractive"][{3 #, 3 # + 1} &, 1]
Out[1]=

Clicking the leaf adds children:

In[2]:=
ResourceFunction["NestTreeInteractive"][Range[3 # - 1, 3 # + 1] &, 1]
Out[2]=

Children can be continually added by clicking the leaves:

In[3]:=
ResourceFunction["NestTreeInteractive"][Range[3 # - 1, 3 # + 1] &, 1]
Out[3]=

Give a function to apply to each new node:

In[4]:=
ResourceFunction["NestTreeInteractive"][{2 #, 2 # + 1} &, 1, clicked]
Out[4]=

Clicking the leaf adds children:

In[5]:=
ResourceFunction["NestTreeInteractive"][ Range[3 # - 1, 3 # + 1] &, 1, clicked]
Out[5]=

Children can be continually added by clicking the leaves:

In[6]:=
ResourceFunction["NestTreeInteractive"][ Range[3 # - 1, 3 # + 1] &, 1, clicked]
Out[6]=

Applications (2) 

Interactively create a Calkin-Wilf tree:

In[7]:=
ResourceFunction["NestTreeInteractive"][ Replace[{m_, n_} :> {{m, m + n}, {m + n, n}}], {1, 1}, Replace[{m_, n_} :> m/n]]
Out[7]=

Interactively create a Stern-Brocot tree:

In[8]:=
ResourceFunction["NestTreeInteractive"][ n |-> Replace[ ContinuedFraction[n], {as___, a_} :> Sort[FromContinuedFraction /@ {{as, a - 1, 2}, {as, a + 1}}]], 1]
Out[8]=

Requirements

Wolfram Language 13.0 (December 2021) or above

Version History

  • 1.0.2 – 04 March 2024
  • 1.0.1 – 19 January 2024
  • 1.0.0 – 12 January 2024

Source Metadata

Related Resources

Author Notes

Unlike NestTree, NestTreeInteractive does not support operations f that return <|…|> or Hold[…].

License Information