---

name: dqmc-generate description: Create HDF5 simulation files for DQMC with specified physical parameters. Use when setting up new simulations, specifying lattice size, interaction strength U, chemical potential mu, temperature (via dt and L), or number of Monte Carlo sweeps.

Generate Simulation Files

Inputs

Outputs

• {prefix}_0.h5, {prefix}_1.h5, ... - HDF5 simulation files
• {prefix}.h5.params - common params HDF5 file

Procedure

Option A: CLI (simple cases)

Copydqmc-util gen Nx=6 Ny=6 U=4.0 mu=0.0 dt=0.1 L=50 Nfiles=4 prefix=data/run/bin

Option B: Python (parameter scans)

Copyfrom dqmc_util import gen_1band_hub

gen_1band_hub.create_batch(
    prefix="data/run/bin", Nfiles=4,
    Nx=6, Ny=6, U=4.0, mu=0.0, tp=0.0, dt=0.1, L=50
)

Choosing dt and L for a target temperature T:

Copyimport numpy as np
T = 0.25  # target temperature
U = 4.0
beta = 1.0 / T
dt = min((0.05/U)**0.5, beta / 10)  # Trotter error constraint
L = int(np.ceil(beta / dt / 5) * 5)  # L must be divisible by n_matmul and period_eqlt (defaults: 5)
dt = beta / L  # recalculate exact dt

Validation

• Files created: ls {prefix}_*.h5 {prefix}.h5.params
• Trotter error check: U * dt^2 <= 0.05

Failure Modes

Do Not

• Overwrite existing simulation files without confirmation
• Ignore the Trotter error bound (U * dt^2 <= 0.05)