Source code for nachos.splitters.random

from nachos.splitters.abstract_splitter import AbstractSplitter
from nachos.similarity_functions import build_similarity_functions as build_sims
from nachos.constraints import build_constraints
from nachos.data.Data import Dataset, InvertedIndex, Split, FactoredSplit
from nachos.data.Data import collapse_factored_split
from nachos.similarity_functions.SimilarityFunctions import SimilarityFunctions
from nachos.constraints.Constraints import Constraints
from nachos.splitters import register
from typing import Optional, List, Tuple
from tqdm import tqdm
import random


[docs]@register("random") class Random(AbstractSplitter):
[docs] @classmethod def build(cls, conf: dict): return cls( build_sims(conf), build_constraints(conf), max_iter=conf['max_iter'], seed=conf['seed'], )
[docs] def __init__(self, sim_fn: SimilarityFunctions, constraints: Constraints, max_iter: int = 100000, seed: int = 0, ): super().__init__(sim_fn, constraints) self.max_iter = max_iter self.seed = seed
[docs] def __call__(self, d: Dataset) -> Tuple[FactoredSplit, List[float]]: ''' Summary: Given a dataset, split according to the Random splitter algorithm. We draw random splits (a train and heldout split) keeping track of the one with the best score and return that split. We draw a random subset of values from each factor independently. Inputs ------------------------- :param d: The dataset to split :type d: Dataset Returns ------------------------- :return: The dataset splits :rtype: FactoredSplit ''' # Set the random seed (in a slightly paranoid way, i.e., everywhere) random.seed(self.seed) d.set_random_seed(self.seed) # First verify that the graph is not complete. # This could take some time. if d.graph is None: d.make_graph(self.sim_fn) if d.check_complete(): raise ValueError("Random Splitting cannot work on a complete graph") # Make the inverted indices d.make_constraint_inverted_index() d.make_factor_inverted_index() # Initialize some values indices, best_split = d.draw_random_split() split = collapse_factored_split(best_split) best_score = self.score(d, split) print(f"Iter 0: Best Score: {best_score:0.4f}") scores = [best_score] for iter_num in tqdm(range(self.max_iter)): indices, split = d.draw_random_split() collapsed_split = collapse_factored_split(split) score = self.score(d, collapsed_split) if score < best_score: best_score = score print(f"Iter {iter_num}: Best Score: {best_score:0.4f}") scores.append(best_score) best_split = split return (collapse_factored_split(best_split), scores)