--- a/dmri.py	Fri Nov 03 12:51:58 2017 -0400
+++ b/dmri.py	Fri Nov 03 13:03:44 2017 -0400
@@ -31,9 +31,9 @@
 fetch_sherbrooke_3shell()
 # MNove inputs to working directory.
 move_directory_files('/home/greg/.dipy', input_dir)
-fdwi = join(input_dir, 'HARDI193.nii.gz')
-fbval = join(input_dir, 'HARDI193.bval')
-fbvec = join(input_dir, 'HARDI193.bvec')
+fdwi = os.path.join(input_dir, 'HARDI193.nii.gz')
+fbval = os.path.join(input_dir, 'HARDI193.bval')
+fbvec = os.path.join(input_dir, 'HARDI193.bvec')
 # Load the dMRI datasets.
 img = nibabel.load(fdwi)
 data = img.get_data()