diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..835c9cb
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "cdsc_ecology_utils"]
+	path = cdsc_ecology_utils
+	url = code:cdsc_ecology_utils
diff --git a/__init__.py b/__init__.py
index dbb8061..393bc3c 100644
--- a/__init__.py
+++ b/__init__.py
@@ -1,2 +1,2 @@
-from .timeseries import load_clusters, load_densities, build_cluster_timeseries
-
+from timeseries import load_clusters, load_densities, build_cluster_timeseries
+from cdsc_ecology_utils import similarity_functions
diff --git a/cdsc_ecology_utils b/cdsc_ecology_utils
new file mode 160000
index 0000000..5b5fdbb
--- /dev/null
+++ b/cdsc_ecology_utils
@@ -0,0 +1 @@
+Subproject commit 5b5fdbb3c02fc9d60a784de5635812bf97020d3e
diff --git a/similarities/cosine_similarities.py b/similarities/cosine_similarities.py
index b9bab17..e1a9efa 100644
--- a/similarities/cosine_similarities.py
+++ b/similarities/cosine_similarities.py
@@ -1,12 +1,12 @@
 import pandas as pd
 import fire
 from pathlib import Path
-from similarities_helper import similarities, column_similarities
+from cdsc_ecology_utils.similarity import similarities, column_similarities
 from functools import partial
 
 def cosine_similarities(infile, term_colname, outfile, min_df=None, max_df=None, included_subreddits=None, topN=500, exclude_phrases=False, from_date=None, to_date=None, tfidf_colname='tf_idf'):
 
-    return similarities(infile=infile, simfunc=column_similarities, term_colname=term_colname, outfile=outfile, min_df=min_df, max_df=max_df, included_subreddits=included_subreddits, topN=topN, exclude_phrases=exclude_phrases,from_date=from_date, to_date=to_date, tfidf_colname=tfidf_colname)
+    return similarities(infile=infile, simfunc=column_similarities, term_colname=term_colname, outfile=outfile, min_df=min_df, max_df=max_df, included_communities=included_subreddits, topN=topN, exclude_phrases=exclude_phrases,from_date=from_date, to_date=to_date, tfidf_colname=tfidf_colname)
 
 # change so that these take in an input as an optional argument (for speed, but also for idf).
 def term_cosine_similarities(outfile, min_df=None, max_df=None, included_subreddits=None, topN=500, exclude_phrases=False, from_date=None, to_date=None):
diff --git a/similarities/lsi_similarities.py b/similarities/lsi_similarities.py
index eb89f55..2704a39 100644
--- a/similarities/lsi_similarities.py
+++ b/similarities/lsi_similarities.py
@@ -1,7 +1,7 @@
 import pandas as pd
 import fire
 from pathlib import Path
-from similarities_helper import *
+from cdsc_ecology_utils.similarity.similarity_functions import lsi_column_similarities, similarities, 
 #from similarities_helper import similarities, lsi_column_similarities
 from functools import partial
 
@@ -30,7 +30,7 @@ def lsi_similarities(inpath, term_colname, outfile, min_df=None, max_df=None, in
 
     simfunc = partial(lsi_column_similarities,n_components=n_components,n_iter=n_iter,random_state=random_state,algorithm=algorithm,lsi_model_save=lsi_model)
 
-    return similarities(inpath=inpath, simfunc=simfunc, term_colname=term_colname, outfile=outfile, min_df=min_df, max_df=max_df, included_subreddits=included_subreddits, topN=topN, from_date=from_date, to_date=to_date, tfidf_colname=tfidf_colname)
+    return similarities(inpath=inpath, simfunc=simfunc, term_colname=term_colname, outfile=outfile, min_df=min_df, max_df=max_df, included_communities=included_subreddits, topN=topN, from_date=from_date, to_date=to_date, tfidf_colname=tfidf_colname)
 
 # change so that these take in an input as an optional argument (for speed, but also for idf).
 def term_lsi_similarities(inpath='/gscratch/comdata/output/reddit_similarity/tfidf/comment_terms_100k.parquet',outfile=None, min_df=None, max_df=None, included_subreddits=None, topN=None, from_date=None, to_date=None, algorithm='arpack', n_components=300,n_iter=5,random_state=1968):
diff --git a/similarities/tfidf.py b/similarities/tfidf.py
index 01b0b20..f17f586 100644
--- a/similarities/tfidf.py
+++ b/similarities/tfidf.py
@@ -1,10 +1,11 @@
 import fire
 from pyspark.sql import SparkSession
 from pyspark.sql import functions as f
-from similarities_helper import tfidf_dataset, build_weekly_tfidf_dataset, select_topN_subreddits
+from cdsc_ecology_utils.similarity.similarity_functions import tfidf_dataset, \
+    build_weekly_tfidf_dataset, select_topN_communities
 
 def _tfidf_wrapper(func, inpath, outpath, topN, term_colname, exclude, included_subreddits):
-    spark = SparkSession.builder.getOrCreate()y
+    spark = SparkSession.builder.getOrCreate()
 
     df = spark.read.parquet(inpath)
 
@@ -13,7 +14,7 @@ def _tfidf_wrapper(func, inpath, outpath, topN, term_colname, exclude, included_
     if included_subreddits is not None:
         include_subs = set(map(str.strip,open(included_subreddits)))
     else:
-        include_subs = select_topN_subreddits(topN)
+        include_subs = select_topN_communities(topN)
 
     dfwriter = func(df, include_subs, term_colname)