| Likely format | Recommended tool |
|---------------|------------------|
| ALPS XML/HDF5 | ALPS Python libraries (alps module) |
| MP2 output (Gaussian, ORCA) | GaussView, Avogadro, or plain text editor |
| Binary MP2 checkpoint | cclib (Python library) |
| Audio (unlikely) | Audacity, ffmpeg |
| Symptom | Likely Cause | Solution |
|---------|--------------|----------|
| File is empty (0 bytes) | Output redirection failed; stdout went to /dev/null | Remove > /dev/null from your job script |
| File contains binary garbage | You wrote an HDF5 or binary restart file to a text handle | Use --output=text flag in ALPS |
| File is truncated mid-line | Cluster ran out of walltime (job killed) | Increase #SBATCH --time=48:00:00 |
| "Permission denied" inside file | MPI ranks tried to write to same file simultaneously | Use MPI-IO or separate output per rank | alps-mp-o1.mp2
To understand the file, we must dissect its nomenclature. This is not random noise; it is structured metadata. | Symptom | Likely Cause | Solution |