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leaves

Determine terminal nodes

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    Syntax

    N = leaves(T)
    [N,K] = leaves(T,"sort")
    N = leaves(T,"dp")
    [N,K] = leaves(T,"sortdp")

    Description

    N = leaves(T) returns the indices of the terminal nodes of the tree T in the column vector N. The nodes are ordered from left to right as in the tree.

    [N,K] = leaves(T,"sort") returns the sorted indices of the terminal nodes of the tree T. M = N(K) are the indices reordered as in the tree, from left to right.

    [N,K] = leaves(T,"sort") and [N,K] = leaves(T,"s") are equivalent.

    N = leaves(T,"dp") returns the depths and positions of the terminal nodes. N(i,1) is the depth and N(i,2) is the position of the ith terminal node.

    [N,K] = leaves(T,"sortdp") returns the depths and positions of the sorted terminal nodes.

    [N,K] = leaves(T,"sortdp") and [N,K] = leaves(T,"sdp") are equivalent.

    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 at indices 4 and 5. Plot the result.

    t = nodejoin(t,5);
t = nodejoin(t,4);
fig = 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.

    Programmatically, in Node Label, change the selected item from Depth_Position to Index.

    plot(t,"setNodeLabel",fig,"Index")

    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.

    List the indices of the terminal nodes.

    tnodes_ind = leaves(t)
    tnodes_ind = 6×1

     7
     8
     4
     5
    13
    14

    List the terminal nodes, this time sorted on the index.

    [tnodes_ind,Ind] = leaves(t,"sort")
    tnodes_ind = 6×1

     4
     5
     7
     8
    13
    14


    Ind = 6×1

     3
     4
     1
     2
     5
     6

    List the depths and positions of the terminal nodes.

    tnodes_depo = leaves(t,"dp")
    tnodes_depo = 6×2

     3     0
     3     1
     2     1
     2     2
     3     6
     3     7

    List the depths and positions again, this time, sorted on depth and position.

    [tnodes_depo,Ind] = leaves(t,"sortdp")
    tnodes_depo = 6×2

     2     1
     2     2
     3     0
     3     1
     3     6
     3     7


    Ind = 6×1

     3
     4
     1
     2
     5
     6

    Input Arguments

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    Tree, specified as a ntree, dtree, or wptree object.

    Output Arguments

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    Terminal node description, returned as a column vector or matrix. The nodes are numbered from left to right as in the tree T. The root index is 0.

    • If N = leaves(T), N is a P-by-1 column vector, where P is the number of terminal nodes in the tree. N(i) is the index of the ith node.

    • If N = leaves(T,"dp"), N is a P-by-2 matrix. N(i,1) is the depth and N(i,2) is the position of the ith node.

    Indices, returned as a vector. The indices K are such that M = N(K) are the terminal indices reordered from left to right.

    Version History

    Introduced before R2006a

    See Also