cdsc_reddit/similarities/top_subreddits_by_comments.py

from pyspark.sql import functions as f
from pyspark.sql import SparkSession
from pyspark.sql import Window

spark = SparkSession.builder.getOrCreate()
conf = spark.sparkContext.getConf()

df = spark.read.parquet("/gscratch/comdata/output/reddit_comments_by_subreddit.parquet")

# remove /u/ pages
df = df.filter(~df.subreddit.like("u_%"))

df = df.groupBy('subreddit').agg(f.count('id').alias("n_comments"))

win = Window.orderBy(f.col('n_comments').desc())
df = df.withColumn('comments_rank', f.rank().over(win))

df = df.toPandas()

df = df.sort_values("n_comments")

df.to_csv('/gscratch/comdata/output/reddit_similarity/subreddits_by_num_comments.csv', index=False)