[AlexsLemonade#229] comparative rnaseq - utils bugfix

utils.py - write_rds accidentally modified its input dataframe; now makes
a copy before changing it. oops.

analyses/comparative-RNASeq-analysis/utils.py

@@ -7,8 +7,6 @@
 import pandas as pd
 import pyreadr
 
-
-
 def read_rds(filepath):
     """Read an RDS-format matrix into a Pandas dataframe.
     Location can be data, scratch, or results.
@@ -22,8 +20,9 @@ def write_rds(df, filepath):
     """Write a pandas dataframe to RDS file in the dir specified.
     Valid locations are scratch or results.
     Index is stored as first column since pyreadr.write_rds drops it otherwise"""
-    df.insert(0, df.index.name, df.index, allow_duplicates=True)
-    pyreadr.write_rds(filepath, df)
+    indexed_df = df.copy()
+    indexed_df.insert(0, indexed_df.index.name, indexed_df.index, allow_duplicates=True)
+    pyreadr.write_rds(filepath, indexed_df)
     # Pyreadr.write_rds fails silently when permissions prevent file write,
     # so trigger an error if our file isn't actually there
     with open(filepath, "rb"):