Command line

daedalus is one executable with a command per task. Every command takes the model sources (.mo files or directories, loaded recursively) and the model's full name:

daedalus <command> [sources...] -m <Model> [options]

Only the classes a model needs are parsed, so pointing at a large library costs little; parsed library files are cached on disk between runs (~/.cache/daedalus; DAEDALUS_CACHE moves it and DAEDALUS_NO_CACHE turns it off).

#Commands

The same compiler is also a Python package, import daedalus, for notebooks and scripts: see Python API.

#Simulating

# Experiment annotation defaults
daedalus simulate library/Daedalus -m Daedalus.Examples.LandingGear.SinkRates -o sink.mat

# Override the interval, tolerance, method and parameters
daedalus simulate library/Daedalus -m Daedalus.Examples.TorqueConverter.StallTest \
    --stop 6 --tol 1e-8 --method dopri5 -p engine.J=0.3 -o stall.mat

# CSV of selected variables
daedalus simulate library/Daedalus -m Daedalus.Examples.QuarterCar.BumpComparison \
    -o bump.csv --vars clean.body.s,aerated.body.s

translated in 11.7 ms; simulated in 7.2 ms (158 steps, 10 rejected (0 Newton), 378 f-evals, 3 jacobians, 2 events)

.mat results use Dymola's dsres layout, so Dymola, OMEdit, DyMat, ModelicaRes and existing post-processing scripts read them.

Add --profile to see where the solver spends its steps and time, and --method auto to let it switch between Dopri5 and BDF; see Performance analyzer and Solvers.

#Libraries

The bundled Daedalus library is a source directory like any other, and so is the Modelica Standard Library:

git clone -b v4.1.0 --depth 1 https://github.com/modelica/ModelicaStandardLibrary msl
daedalus simulate msl/Modelica msl/ModelicaServices msl/Complex.mo \
    -m Modelica.Mechanics.Rotational.Examples.CoupledClutches -o clutches.mat

-L DIR adds a library directory the same way, and DAEDALUS_LIB (or --lib) points at the bundled library.

#Steady states and trim

daedalus steady crates/daedalus-core/tests/models/steady.mo -m Steady.Pendulum \
    --free tau --target angle=0.5

trim of Steady.Pendulum at t = 0 (2 Newton iterations, residual 0.000e0)

states:
  phi = 0.5
  w   = 0

free variables:
  tau = 3.7625316269657856

targets:
  angle = 0.5 (target 0.5)

eigenvalues of the state Jacobian (stable):
  -2.343750e-1 - 3.272067e0i
  -2.343750e-1 + 3.272067e0i

The torque that holds the pendulum at 0.5 rad is m·g·L·sin(0.5) = 3.76 N·m, and the equilibrium is stable. Without --free and --target, steady finds the equilibrium for the inputs as they are. See Scripts and steady states.

#Scripts

daedalus run regression.mos --msl ~/ModelicaStandardLibrary

runs a Dymola or OpenModelica .mos script: loading files and libraries, translating, simulateModel and simulate, parameter sweeps with simulateExtendedModel, linearizeModel, steadyState and trim, with loops and conditionals. See Scripts and steady states.

#Testing a whole library

daedalus test-library library/Daedalus -m Daedalus

Each model runs in its own process, in parallel (--jobs N, default: all cores), with a time limit (--timeout S, default 60). CI runs this on every pull request, and a nightly job runs the MSL examples against their reference results (see Modelica Standard Library).

#Options

#Performance

The benchmark is tools/gen_chain.py: a chain of N masses and spring-dampers driven by a sine force, a stiff system with 2N states, simulated for 1 s with BDF at tolerance 1e-6.

python3 tools/gen_chain.py 2000 > chain.mo
daedalus simulate library/Daedalus chain.mo -m Chain --stop 0.2 -o chain.mat