By name: dqmc-advanced description: Advanced DQMC features including unequal-time measurements, analytic continuation, and queue system internals. Use when enabling dynamical correlations, performing MaxEnt continuation, or understanding HDF5 data structure.
Advanced Topics
Unequal-Time Measurements
Enable by setting period_uneqlt > 0 during file generation:
dqmc-util gen period_uneqlt=8 ...
Required for:
nnrw0,zzrw0- Zero-frequency susceptibilitiesdwq0t- D-wave pair susceptibility- Any time-dependent correlation functions
Note: Unequal-time measurements significantly increase runtime and memory usage.
Analytic Continuation
Use maximum entropy for continuing imaginary-time data to real frequencies:
from dqmc_util import maxent
# Solve G = K A given:
# - G: binned data, shape (nbin, ntau)
# - K: kernel, shape (ntau, nw)
# - m: default model, shape (nw,)
A_omega = maxent.calc_A(G, K, m)
HDF5 File Structure
/metadata/ # Model info (mu, Nx, Ny, beta)
/params/ # Simulation parameters, precomputed matrices
/state/ # RNG state, sweep number, aux field config
/meas_eqlt/ # Equal-time measurements (n_sample, sign, den, ...)
/meas_uneqlt/ # Unequal-time measurements (optional)
Queue System Internals
The sharded queue uses:
- 128 shards to avoid lock contention on distributed filesystems
- Atomic
rename()operations for task claiming - Symlinks moved:
todo/->running/->done/ - Checkpointed jobs returned to
todo/for resumption