[Error] generator raised StopIteration

[HoaSoup]

Hello,

I was running this code:

u = mda.Universe(topology_file, trajectory_file)
    average = align.AverageStructure(u, u, select=mda_rmsf_avg_struc_sel,
                                     ref_frame=0).run()
    ref = average.results.universe
    aligner = align.AlignTraj(u, ref,
                              select=mda_rmsf_avg_struc_sel,
                              filename=trajectory_file,
                              in_memory=False).run()

when I hit this error:

Exception has occurred: RuntimeError
generator raised StopIteration
StopIteration: 

The above exception was the direct cause of the following exception:

  File "/home/hoalt/code/master-pipeline/src/packages/md/md/analysis.py", line 230, in log_RMSF
    in_memory=False).run()
  File "/home/hoalt/code/master-pipeline/src/packages/md/md/analysis.py", line 722, in analyze_trajectory
    log_RMSF(trajectory_file=trajectory_file,
  File "/home/hoalt/code/master-pipeline/src/packages/md/md/analysis.py", line 844, in main
    analyze_trajectory(md_outdir=args.md_outdir,
  File "/home/hoalt/tool/miniforge3/envs/masterpipeline/bin/md_analyze", line 6, in <module>
    sys.exit(main())
RuntimeError: generator raised StopIteration

No idea what this was about. Any help is appreciated!

Best regards,
Hoa