Analyze Results
Inputs
- Directory containing
bin_*.h5files (completed simulations) - Observable names (see table below)
Outputs
- Dictionary with parameters and
(mean, stderr)tuples for each observable
Procedure
Basic analysis:
python1from dqmc_util import analyze_hub 2 3data = analyze_hub.get("data/run/", "sign", "den", "zzr") 4 5print(f"sign = {data['sign'][0]:.4f} +/- {data['sign'][1]:.4f}") 6print(f"density = {data['den'][0]:.4f} +/- {data['den'][1]:.4f}")
Available observables:
| Name | Description | Requires |
|---|---|---|
sign | Fermion sign | - |
den | Density <n> | - |
docc | Double occupancy <n_up n_down> | - |
gr, gk | Green's function (real/k-space) | - |
nnr, nnq | Density correlator / structure factor | - |
zzr, zzq | Spin-z correlator / structure factor | - |
xxr | Spin-x correlator | - |
swq0 | S-wave pair structure factor | - |
nnrw0, zzrw0 | Zero-freq susceptibilities | period_uneqlt > 0 |
dwq0t | D-wave pair susceptibility | period_uneqlt > 0 |
Collect from multiple directories:
python1import os 2 3def collect_results(base_dir, observables): 4 results = [] 5 for subdir in sorted(os.listdir(base_dir)): 6 path = os.path.join(base_dir, subdir) 7 if os.path.isdir(path): 8 try: 9 results.append(analyze_hub.get(path + "/", *observables)) 10 except Exception as e: 11 print(f"Skipping {path}: {e}") 12 return results
Compute derived quantities:
python1# Magnetic moment squared from spin correlator 2path = "data/run/" 3data = analyze_hub.get(path, "zzr") 4mz2 = 4 * data["zzr"][0][0, 0] # [0] = mean, shape (Ny, Nx) 5mz2_err = 4 * data["zzr"][1][0, 0] # [1] = stderr
Validation
- Errorbar on sign is significantly less than mean. Otherwise, sign problem is too severe.
- Errorbars on observable are reasonable (not >> mean)
Failure Modes
| Symptom | Cause | Recovery |
|---|---|---|
| KeyError for observable | Observable not computed | Check period_uneqlt setting |
| "No files found" | Wrong path or no bin_*.h5 | Verify directory structure |
| Large error bars | Insufficient statistics | Run more sweeps or bins |