skbio.tree.BPTree.first_child

BPTree.first_child(i)

Index of the first (leftmost) child of a node.

Parameters:

iint

Index of the node to evaluate.

Returns:

int

Index of the first child of node i, or 0 if i is a tip (0 is the root, which can never be a child).

See also

last_child

skbio.tree.TreeNode

Notes

Returns an integer index into the parentheses bit array, not a node object. Corresponds to accessing children[0] on a TreeNode.