import fire
from itertools import islice
from pathlib import Path
-
-min_df = 1000
+from similarities_helper import build_cosine_similarities
spark = SparkSession.builder.getOrCreate()
conf = spark.sparkContext.getConf()
# outfile = '/gscratch/comdata/users/nathante/test_similarities_500.feather'; min_df = None; included_subreddits=None; similarity_threshold=0;
-def spark_similarities(outfile, min_df = None, included_subreddits=None, similarity_threshold=0):
+def term_cosine_similarities(outfile, min_df = None, included_subreddits=None, similarity_threshold=0, topN=500, exclude_phrases=True):
'''
Compute similarities between subreddits based on tfi-idf vectors of comment texts
where to output csv and feather outputs
'''
+ print(outfile)
+ print(exclude_phrases)
+
tfidf = spark.read.parquet('/gscratch/comdata/users/nathante/subreddit_tfidf.parquet')
if included_subreddits is None:
- included_subreddits = list(islice(open("/gscratch/comdata/users/nathante/cdsc-reddit/top_25000_subs_by_comments.txt"),500))
- included_subreddits = [s.strip('\n') for s in included_subreddits]
+ included_subreddits = list(islice(open("/gscratch/comdata/users/nathante/cdsc-reddit/top_25000_subs_by_comments.txt"),topN))
+ included_subreddits = {s.strip('\n') for s in included_subreddits}
else:
included_subreddits = set(open(included_subreddits))
- if min_df is None:
- min_df = 0.1 * len(included_subreddits)
-
- tfidf = tfidf.filter(f.col("subreddit").isin(included_subreddits))
-
- # reset the subreddit ids
- sub_ids = tfidf.select('subreddit_id').distinct()
- sub_ids = sub_ids.withColumn("subreddit_id_new",f.row_number().over(Window.orderBy("subreddit_id")))
- tfidf = tfidf.join(sub_ids,'subreddit_id')
-
- # only use terms in at least min_df included subreddits
- new_count = tfidf.groupBy('term_id').agg(f.count('term_id').alias('new_count'))
- term_ids = term_ids.join(new_count,'term_id')
- term_ids = term_ids.filter(new_count >= min_df)
+ if exclude_phrases == True:
+ tfidf = tfidf.filter(~f.col(term).contains("_"))
- # reset the term ids
- term_ids = tfidf.select('term_id').distinct()
- term_ids = term_ids.withColumn("term_id_new",f.row_number().over(Window.orderBy("term_id")))
- tfidf = tfidf.join(term_ids,'term_id')
+ sim_dist, tfidf = cosine_similarities(tfidf, 'term', min_df, include_subreddits, similarity_threshold)
- # step 1 make an rdd of entires
- # sorted by (dense) spark subreddit id
- entries = tfidf.select(f.col("term_id_new")-1,f.col("subreddit_id_new")-1,"tf_idf").rdd
-
- # step 2 make it into a distributed.RowMatrix
- coordMat = CoordinateMatrix(entries)
-
- # this needs to be an IndexedRowMatrix()
- mat = coordMat.toRowMatrix()
+ p = Path(outfile)
- #goal: build a matrix of subreddit columns and tf-idfs rows
- sim_dist = mat.columnSimilarities(threshold=similarity_threshold)
+ output_feather = Path(str(p).replace("".join(p.suffixes), ".feather"))
+ output_csv = Path(str(p).replace("".join(p.suffixes), ".csv"))
+ output_parquet = Path(str(p).replace("".join(p.suffixes), ".parquet"))
- print(sim_dist.numRows(), sim_dist.numCols())
+ sim_dist.entries.toDF().write.parquet(str(output_parquet),mode='overwrite',compression='snappy')
+
+ spark.stop()
#instead of toLocalMatrix() why not read as entries and put strait into numpy
- sim_entries = sim_dist.entries.collect()
-
- sim_entries = pd.DataFrame([{'i':me.i,'j':me.j,'value':me.value} for me in sim_entries])
+ sim_entries = pd.read_parquet(output_parquet)
df = tfidf.select('subreddit','subreddit_id_new').distinct().toPandas()
-
+ df['subreddit_id_new'] = df['subreddit_id_new'] - 1
df = df.sort_values('subreddit_id_new').reset_index(drop=True)
-
df = df.set_index('subreddit_id_new')
similarities = sim_entries.join(df, on='i')
- similarities = sim_entries.rename(columns={'subreddit':"subreddit_i"})
- similarities = sim_entries.join(df, on='j')
- similarities = sim_entries.rename(columns={'subreddit':"subreddit_j"})
-
- p = Path(outfile)
- output_feather = Path(str(p).replace("".join(p.suffixes), ".feather"))
- output_csv = Path(str(p).replace("".join(p.suffixes), ".csv"))
+ similarities = similarities.rename(columns={'subreddit':"subreddit_i"})
+ similarities = similarities.join(df, on='j')
+ similarities = similarities.rename(columns={'subreddit':"subreddit_j"})
- pyarrow.write_feather(similarities,output_feather)
- pyarrow.write_csv(similarities,output_csv)
+ similarities.write_feather(output_feather)
+ similarities.write_csv(output_csv)
return similarities
if __name__ == '__main__':
- fire.Fire(spark_similarities)
+ fire.Fire(term_cosine_similarities)