davda54/dependency_decoding

Chu-Lui-Edmonds decoding extracted from TurboParser

Chu-Liu-Edmonds dependency decoding

This package wraps the Chu-Liu-Edmonds maximum spanning algorithm from TurboParser for use within Python.

It provides a function chu_liu_edmonds which accepts a $N \times N$ score matrix as argument, where N is the sentence length, including the artificial root node. The $i,j$-th cell is the score for the edge j->i. In other words, a row gives the scores for the different heads of a dependent.

A np.nan cell value informs the algorithm to skip the edge.

Example usage:

import numpy as np
from dependency_decoding import chu_liu_edmonds

np.random.seed(42)
score_matrix = np.random.rand(3, 4)
heads, tree_score = chu_liu_edmonds(score_matrix)
print(heads, tree_score)

Install

Install directly from Github as shown below:

pip install git+https://github.com/andersjo/dependency_decoding