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depo2ind

Node depth-position to node index

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    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.

    example

    Examples

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    Open Live Script

    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)

    Figure contains an axes object and an object of type uimenu. The axes object with title Tree Decomposition contains 21 objects of type line, text.

    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
      ⋮

    Input Arguments

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    Order of a tree, specified as a positive integer.

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

    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 ≤ ordD-1.

    Output Arguments

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

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

    Note

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

    Version History

    Introduced before R2006a

    See Also