#!/usr/bin/python
# -*- coding: utf-8 -*-
from __future__ import annotations
import collections
import itertools
import random
import sys
import warnings
from typing import Iterator, Tuple
import numpy
import dedupe
from dedupe._typing import (
Data,
Literal,
RecordDict,
RecordDictPair,
RecordID,
TrainingData,
)
from dedupe.canonical import getCanonicalRep
from dedupe.core import unique
IndicesIterator = Iterator[Tuple[int, int]]
def randomPairs(n_records: int, sample_size: int) -> IndicesIterator:
"""
Return random combinations of indices for a square matrix of size n
records. For a discussion of how this works see
http://stackoverflow.com/a/14839010/98080
"""
n: int = n_records * (n_records - 1) // 2
if not sample_size:
return iter([])
elif sample_size >= n:
random_pairs = numpy.arange(n)
else:
try:
random_pairs = numpy.array(
random.sample(range(n), sample_size), dtype=numpy.uint
)
except OverflowError:
return randomPairsWithReplacement(n_records, sample_size)
b: int = 1 - 2 * n_records
i = (-b - 2 * numpy.sqrt(2 * (n - random_pairs) + 0.25)) // 2
i = i.astype(numpy.uint)
j = random_pairs + i * (b + i + 2) // 2 + 1
j = j.astype(numpy.uint)
return zip(i, j)
def randomPairsMatch(
n_records_A: int, n_records_B: int, sample_size: int
) -> IndicesIterator:
"""
Return random combinations of indices for record list A and B
"""
n: int = n_records_A * n_records_B
if not sample_size:
return iter([])
elif sample_size >= n:
random_pairs = numpy.arange(n)
else:
random_pairs = numpy.array(random.sample(range(n), sample_size))
i, j = numpy.unravel_index(random_pairs, (n_records_A, n_records_B))
return zip(i, j)
def randomPairsWithReplacement(n_records: int, sample_size: int) -> IndicesIterator:
# If the population is very large relative to the sample
# size than we'll get very few duplicates by chance
warnings.warn("The same record pair may appear more than once in the sample")
try:
random_indices = numpy.random.randint(n_records, size=sample_size * 2)
except (OverflowError, ValueError):
max_int: int = numpy.iinfo("int").max
warnings.warn(
"Asked to sample pairs from %d records, will only sample pairs from first %d records"
% (n_records, max_int)
)
random_indices = numpy.random.randint(max_int, size=sample_size * 2)
random_indices = random_indices.reshape((-1, 2))
random_indices.sort(axis=1)
return ((p.item(), q.item()) for p, q in random_indices)
def _print(*args) -> None:
print(*args, file=sys.stderr)
LabeledPair = Tuple[RecordDictPair, Literal["match", "distinct", "unsure"]]
def _mark_pair(deduper: dedupe.api.ActiveMatching, labeled_pair: LabeledPair) -> None:
record_pair, label = labeled_pair
examples: TrainingData = {"distinct": [], "match": []}
if label == "unsure":
# See https://github.com/dedupeio/dedupe/issues/984 for reasoning
examples["match"].append(record_pair)
examples["distinct"].append(record_pair)
else:
# label is either "match" or "distinct"
examples[label].append(record_pair)
deduper.mark_pairs(examples)
[docs]def console_label(deduper: dedupe.api.ActiveMatching) -> None: # pragma: no cover
"""
Train a matcher instance (Dedupe, RecordLink, or Gazetteer) from the command line.
Example
.. code:: python
> deduper = dedupe.Dedupe(variables)
> deduper.prepare_training(data)
> dedupe.console_label(deduper)
"""
finished = False
use_previous = False
fields = unique(var.field for var in deduper.data_model.primary_variables)
buffer_len = 1 # Max number of previous operations
unlabeled: list[RecordDictPair] = []
labeled: list[LabeledPair] = []
n_match = len(deduper.training_pairs["match"])
n_distinct = len(deduper.training_pairs["match"])
while not finished:
if use_previous:
record_pair, label = labeled.pop(0)
if label == "match":
n_match -= 1
elif label == "distinct":
n_distinct -= 1
use_previous = False
else:
try:
if not unlabeled:
unlabeled = deduper.uncertain_pairs()
record_pair = unlabeled.pop()
except IndexError:
break
for record in record_pair:
for field in fields:
line = "%s : %s" % (field, record[field])
_print(line)
_print()
_print(f"{n_match}/10 positive, {n_distinct}/10 negative")
_print("Do these records refer to the same thing?")
valid_response = False
user_input = ""
while not valid_response:
if labeled:
_print("(y)es / (n)o / (u)nsure / (f)inished / (p)revious")
valid_responses = {"y", "n", "u", "f", "p"}
else:
_print("(y)es / (n)o / (u)nsure / (f)inished")
valid_responses = {"y", "n", "u", "f"}
user_input = input()
if user_input in valid_responses:
valid_response = True
if user_input == "y":
labeled.insert(0, (record_pair, "match"))
n_match += 1
elif user_input == "n":
labeled.insert(0, (record_pair, "distinct"))
n_distinct += 1
elif user_input == "u":
labeled.insert(0, (record_pair, "unsure"))
elif user_input == "f":
_print("Finished labeling")
finished = True
elif user_input == "p":
use_previous = True
unlabeled.append(record_pair)
while len(labeled) > buffer_len:
_mark_pair(deduper, labeled.pop())
for labeled_pair in labeled:
_mark_pair(deduper, labeled_pair)
[docs]def training_data_link(
data_1: Data, data_2: Data, common_key: str, training_size: int = 50000
) -> TrainingData: # pragma: nocover
"""
Construct training data for consumption by the func:`mark_pairs`
method from already linked datasets.
Args:
data_1: Dictionary of records from first dataset, where the
keys are record_ids and the values are dictionaries
with the keys being field names
data_2: Dictionary of records from second dataset, same form as
data_1
common_key: The name of the record field that uniquely identifies
a match
training_size: the rough limit of the number of training examples,
defaults to 50000
.. note::
Every match must be identified by the sharing of a common key.
This function assumes that if two records do not share a common key
then they are distinct records.
"""
identified_records: dict[str, tuple[list[RecordID], list[RecordID]]]
identified_records = collections.defaultdict(lambda: ([], []))
matched_pairs: set[tuple[RecordID, RecordID]] = set()
distinct_pairs: set[tuple[RecordID, RecordID]] = set()
for record_id, record in data_1.items():
identified_records[record[common_key]][0].append(record_id)
for record_id, record in data_2.items():
identified_records[record[common_key]][1].append(record_id)
for keys_1, keys_2 in identified_records.values():
if keys_1 and keys_2:
matched_pairs.update(itertools.product(keys_1, keys_2))
keys_1 = list(data_1.keys())
keys_2 = list(data_2.keys())
random_pairs = [
(keys_1[i], keys_2[j])
for i, j in randomPairsMatch(len(data_1), len(data_2), training_size)
]
distinct_pairs = {pair for pair in random_pairs if pair not in matched_pairs}
matched_records = [(data_1[key_1], data_2[key_2]) for key_1, key_2 in matched_pairs]
distinct_records = [
(data_1[key_1], data_2[key_2]) for key_1, key_2 in distinct_pairs
]
training_pairs: TrainingData
training_pairs = {"match": matched_records, "distinct": distinct_records}
return training_pairs
[docs]def training_data_dedupe(
data: Data, common_key: str, training_size: int = 50000
) -> TrainingData: # pragma: nocover
"""
Construct training data for consumption by the func:`mark_pairs`
method from an already deduplicated dataset.
Args:
data: Dictionary of records where the keys are record_ids and
the values are dictionaries with the keys being field names
common_key: The name of the record field that uniquely identifies
a match
training_size: the rough limit of the number of training examples,
defaults to 50000
.. note::
Every match must be identified by the sharing of a common key.
This function assumes that if two records do not share a common key
then they are distinct records.
"""
identified_records: dict[str, list[RecordID]]
identified_records = collections.defaultdict(list)
matched_pairs: set[tuple[RecordID, RecordID]] = set()
distinct_pairs: set[tuple[RecordID, RecordID]] = set()
unique_record_ids: set[RecordID] = set()
# a list of record_ids associated with each common_key
for record_id, record in data.items():
unique_record_ids.add(record_id)
identified_records[record[common_key]].append(record_id)
# all combinations of matched_pairs from each common_key group
for record_ids in identified_records.values():
if len(record_ids) > 1:
matched_pairs.update(itertools.combinations(sorted(record_ids), 2))
# calculate indices using dedupe.core.randomPairs to avoid
# the memory cost of enumerating all possible pairs
unique_record_ids_l = list(unique_record_ids)
pair_indices = randomPairs(len(unique_record_ids), training_size)
distinct_pairs = set()
for i, j in pair_indices:
distinct_pairs.add((unique_record_ids_l[i], unique_record_ids_l[j]))
distinct_pairs -= matched_pairs
matched_records = [(data[key_1], data[key_2]) for key_1, key_2 in matched_pairs]
distinct_records = [(data[key_1], data[key_2]) for key_1, key_2 in distinct_pairs]
training_pairs: TrainingData
training_pairs = {"match": matched_records, "distinct": distinct_records}
return training_pairs
[docs]def canonicalize(record_cluster: list[RecordDict]) -> RecordDict: # pragma: nocover
"""
Constructs a canonical representation of a duplicate cluster by
finding canonical values for each field
Args:
record_cluster: A list of records within a duplicate cluster, where
the records are dictionaries with field
names as keys and field values as values
"""
return getCanonicalRep(record_cluster)
