Struct louds_rs::Louds

pub struct Louds { /* private fields */ }

LOUDS (Level-Order Unary Degree Sequence).

This class can handle tree structure of virtually arbitrary number of nodes.

In fact, N (number of nodes in the tree) is designed to be limited to: N < 2^64 / 2, while each node is represented in 2bits in average.
It should be enough for almost all usecases since a binary data of length of 2^63 consumes 2^20 = 1,048,576 TB (terabytes), which is hard to handle by state-of-the-art computer architecture.

Implementations

impl Louds

pub fn node_num_to_index(&self, node_num: LoudsNodeNum) -> LoudsIndex

Panics

node_num does not exist in this LOUDS.

pub fn index_to_node_num(&self, index: LoudsIndex) -> LoudsNodeNum

Panics

index does not point to any node in this LOUDS.

pub fn child_to_parent(&self, index: LoudsIndex) -> LoudsNodeNum

Panics

• index does not point to any node in this LOUDS.
• index == 0: (node#1 is root and doesn’t have parent)

pub fn child_to_ancestors(&self, child: LoudsNodeNum) -> AncestorNodeIter<'_>

Return an iterator to the child and its ancestors’ node numbers.

pub fn parent_to_children(&self, node_num: LoudsNodeNum) -> Vec<LoudsIndex>

Panics

node_num does not exist in this LOUDS.

pub fn parent_to_children_indices( &self, node_num: LoudsNodeNum ) -> ChildIndexIter<'_>

Panics

node_num does not exist in this LOUDS.

pub fn parent_to_children_nodes( &self, node_num: LoudsNodeNum ) -> ChildNodeIter<'_>

Panics

node_num does not exist in this LOUDS.

Trait Implementations

impl Clone for Louds

fn clone(&self) -> Louds

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Louds

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&[bool]> for Louds

fn from(bits: &[bool]) -> Self

Prepares for building Louds from LBS (LOUDS Bit vector).

It takes O(log bits) time for validation.

Panics

Same as Louds::from::<&str>().

impl From<&str> for Louds

fn from(s: &str) -> Self

Prepares for building Louds from LBS (LOUDS Bit vector).

It takes O(log s) time for validation.

Panics

If s does not represent a LOUDS tree. s must satisfy the following condition as LBS.

• Starts from “10”
• In the range of [0, i] for any i (< length of LBS);
  • the number of ‘0’ <= the number of ‘1’ + 1, because:
    • Each node, including virtual root (node num = 0), has one ‘0’.
    • Each node is derived from one ‘1’.
• In the range of [0, length of LBS);
  • the number of ‘0’ == the number of ‘1’ + 1