Running simulations¶

idfpy.sim runs the EnergyPlus executable, so EnergyPlus must be installed. By default the energyplus command on PATH is used; pass energyplus_bin to choose another installation.

One simulation¶

from pathlib import Path

from idfpy.sim import simulate

result = simulate(
    Path('model.idf'),
    weather=Path('weather.epw'),
    output_dir=Path('results'),
    annual=True,          # -a
    readvars=True,        # -r, convert ESO output to CSV
)

simulate also accepts an in-memory IDF. It is written to a temporary file first, so output_dir is required in that case:

result = simulate(idf, weather=Path('weather.epw'), output_dir=Path('results'))

HVACTemplate objects are expanded with ExpandObjects unless you pass expand_objects=False.

Reading the result¶

result.success        # True when EnergyPlus exited with code 0
result.return_code
result.end_message    # contents of eplusout.end
result.err            # ErrSummary parsed from eplusout.err, or None

if result.err:
    print(result.err.warning_count, result.err.severe_count, result.err.has_fatal)

Many simulations¶

simulate_batch runs jobs concurrently, by default on all but one CPU core.

from idfpy.sim import SimJob, simulate_batch

jobs = [
    SimJob(idf=Path(f'variant_{i}.idf'), weather=Path('weather.epw'),
           output_dir=Path(f'results/{i}'))
    for i in range(8)
]
results = simulate_batch(jobs, max_concurrent=4)
failed = [job.idf for job, r in zip(jobs, results) if not r.success]

Inside an existing event loop use async_simulate and async_simulate_batch, which take the same arguments.