depo2ind

R2026b

Node depth-position to node index

Syntax

n = depo2ind(ord,[d,p])

Description

depo2ind is a tree-management utility.

n = depo2ind(ord,[d,p]) returns, for a tree of order ord, the indices n of the nodes whose depths and positions are encoded within d and p.

The nodes are numbered from left to right and from top to bottom. The root index is 0.

Examples

Convert Depth-Position to Node Index

Create a binary tree of depth 3.

ord = 2;
t = ntree(ord,3);

Merge the nodes of indices 4 and 5. Plot the tree.

t = nodejoin(t,5);
t = nodejoin(t,4);
plot(t)

Use the allnodes function to obtain the depth-position of the tree nodes.

aln_depo = allnodes(t,"deppos");

Convert every depth-position to a node index.

aln_ind = depo2ind(ord,aln_depo);
[aln_depo aln_ind]

ans = 11×3

     0     0     0
     1     0     1
     1     1     2
     2     0     3
     2     1     4
     2     2     5
     2     3     6
     3     0     7
     3     1     8
     3     6    13
     3     7    14

Input Arguments

ord — Order of a tree

positive integer

Order of a tree, specified as a positive integer.

Example: A binary tree is a tree of order 2.

d,p — Depths and positions

pair of column vectors

Depths and positions (at those depths) for nodes in a tree of order ord, specified as a pair of column vectors with nonnegative integer entries. The vectors d and p must have the same length.

The values of depths D and positions P must be such that D ≥0 and 0≤ P ≤ ord^D-1.

Output Arguments

n — Node indices

column vector

Node indices, returned as a column vector with nonnegative integer entries.

The values of the indices N are such that 0 ≤ N < (ord^max(d)+1-1)/(ord–1), where d are the depths.

Note

For a column vector X, we have depo2ind(ord,X) = X.

Extended Capabilities

Thread-Based Environment

Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

The depo2ind function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Version History

Introduced before R2006a

R2026b: Use thread-based environments

You can use depo2ind in thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.