<s> from __future__ import division <EOL> from builtins import range , zip <EOL> from future . utils import viewitems <EOL> from collections import deque <EOL> import random <EOL> import functools <EOL> import itertools <EOL> import warnings <EOL> from collections import defaultdict <EOL> def blockedSample ( sampler , sample_size , predicates , * args ) : <EOL> blocked_sample = set ( ) <EOL> remaining_sample = sample_size - len ( blocked_sample ) <EOL> previous_sample_size = <NUM_LIT:0> <EOL> while remaining_sample and predicates : <EOL> random . shuffle ( predicates ) <EOL> new_sample = sampler ( remaining_sample , <EOL> predicates , <EOL> * args ) <EOL> filtered_sample = ( subsample for subsample <EOL> in new_sample if subsample ) <EOL> blocked_sample . update ( itertools . chain . from_iterable ( filtered_sample ) ) <EOL> growth = len ( blocked_sample ) - previous_sample_size <EOL> growth_rate = growth / remaining_sample <EOL> remaining_sample = sample_size - len ( blocked_sample ) <EOL> previous_sample_size = len ( blocked_sample ) <EOL> if growth_rate < <NUM_LIT> : <EOL> warnings . warn ( "<STR_LIT>" <EOL> "<STR_LIT>" <EOL> % ( sample_size , len ( blocked_sample ) ) ) <EOL> break <EOL> predicates = [ pred for pred , pred_sample <EOL> in zip ( predicates , new_sample ) <EOL> if pred_sample or pred_sample is None ] <EOL> return blocked_sample <EOL> def dedupeSamplePredicates ( sample_size , predicates , items ) : <EOL> n_items = len ( items ) <EOL> for subsample_size , predicate in subsample ( sample_size , predicates ) : <EOL> if not subsample_size : <EOL> yield None <EOL> continue <EOL> items . rotate ( random . randrange ( n_items ) ) <EOL> items . reverse ( ) <EOL> yield dedupeSamplePredicate ( subsample_size , <EOL> predicate , <EOL> items ) <EOL> def dedupeSamplePredicate ( subsample_size , predicate , items ) : <EOL> sample = [ ] <EOL> block_dict = { } <EOL> predicate_function = predicate . func <EOL> field = predicate . field <EOL> for pivot , ( index , record ) in enumerate ( items ) : <EOL> column = record [ field ] <EOL> if not column : <EOL> continue <EOL> if pivot == <NUM_LIT> : <EOL> if len ( block_dict ) + len ( sample ) < <NUM_LIT:10> : <EOL> return sample <EOL> block_keys = predicate_function ( column ) <EOL> for block_key in block_keys : <EOL> if block_key not in block_dict : <EOL> block_dict [ block_key ] = index <EOL> else : <EOL> pair = sort_pair ( block_dict . pop ( block_key ) , index ) <EOL> sample . append ( pair ) <EOL> subsample_size -= <NUM_LIT:1> <EOL> if subsample_size : <EOL> break <EOL> else : <EOL> return sample <EOL> else : <EOL> return sample <EOL> def linkSamplePredicates ( sample_size , predicates , items1 , items2 ) : <EOL> n_1 = len ( items1 ) <EOL> n_2 = len ( items2 ) <EOL> for subsample_size , predicate in subsample ( sample_size , predicates ) : <EOL> if not subsample_size : <EOL> yield None <EOL> continue <EOL> try : <EOL> items1 . rotate ( random . randrange ( n_1 ) ) <EOL> items2 . rotate ( random . randrange ( n_2 ) ) <EOL> except ValueError : <EOL> raise ValueError ( "<STR_LIT>" ) <EOL> try : <EOL> items1 . reverse ( ) <EOL> items2 . reverse ( ) <EOL> except AttributeError : <EOL> items1 = deque ( reversed ( items1 ) ) <EOL> items2 = deque ( reversed ( items2 ) ) <EOL> yield linkSamplePredicate ( subsample_size , predicate , items1 , items2 ) <EOL> def linkSamplePredicate ( subsample_size , predicate , items1 , items2 ) : <EOL> sample = [ ] <EOL> predicate_function = predicate . func <EOL> field = predicate . field <EOL> red = defaultdict ( list ) <EOL> blue = defaultdict ( list ) <EOL> for i , ( index , record ) in enumerate ( interleave ( items1 , items2 ) ) : <EOL> if i == <NUM_LIT> : <EOL> if min ( len ( red ) , len ( blue ) ) + len ( sample ) < <NUM_LIT:10> : <EOL> return sample <EOL> column = record [ field ] <EOL> if not column : <EOL> red , blue = blue , red <EOL> continue <EOL> block_keys = predicate_function ( column ) <EOL> for block_key in block_keys : <EOL> if blue . get ( block_key ) : <EOL> pair = sort_pair ( blue [ block_key ] . pop ( ) , index ) <EOL> sample . append ( pair ) <EOL> subsample_size -= <NUM_LIT:1> <EOL> if subsample_size : <EOL> break <EOL> else : <EOL> return sample <EOL> else : <EOL> red [ block_key ] . append ( index ) <EOL> red , blue = blue , red <EOL> for index , record in itertools . islice ( items2 , len ( items1 ) ) : <EOL> column = record [ field ] <EOL> if not column : <EOL> continue <EOL> block_keys = predicate_function ( column ) <EOL> for block_key in block_keys : <EOL> if red . get ( block_key ) : <EOL> pair = sort_pair ( red [ block_key ] . pop ( ) , index ) <EOL> sample . append ( pair ) <EOL> subsample_size -= <NUM_LIT:1> <EOL> if subsample_size : <EOL> break <EOL> else : <EOL> return sample <EOL> return sample <EOL> def evenSplits ( total_size , num_splits ) : <EOL> avg = total_size / num_splits <EOL> split = <NUM_LIT:0> <EOL> for _ in range ( num_splits ) : <EOL> split += avg - int ( split ) <EOL> yield int ( split ) <EOL> def subsample ( total_size , predicates ) : <EOL> splits = evenSplits ( total_size , len ( predicates ) ) <EOL> for split , predicate in zip ( splits , predicates ) : <EOL> yield split , predicate <EOL> def interleave ( * iterables ) : <EOL> return itertools . chain . from_iterable ( zip ( * iterables ) ) <EOL> def sort_pair ( a , b ) : <EOL> if a > b : <EOL> return ( b , a ) <EOL> else : <EOL> return ( a , b ) <EOL> def randomDeque ( data ) : <EOL> data_q = deque ( random . sample ( viewitems ( data ) , len ( data ) ) ) <EOL> return data_q <EOL> dedupeBlockedSample = functools . partial ( blockedSample , dedupeSamplePredicates ) <EOL> linkBlockedSample = functools . partial ( blockedSample , linkSamplePredicates ) </s>
