CTFlows.jl

CTFlows.jl is the flow integration layer of the control-toolbox ecosystem. Given a dynamical system — a vector field, a Hamiltonian, or a Hamiltonian vector field — it builds a callable flow that integrates the system from any initial condition to any final time, with a pluggable ODE solver and optional automatic differentiation.

Quick start

using CTFlows
using CTBase.Data, CTFlows.Flows, CTFlows.Trajectories
import OrdinaryDiffEqTsit5   # activates the SciML integrator extension

# 1. Wrap the dynamics
vf = Data.VectorField(x -> -x)          # autonomous, fixed, out-of-place

# 2. Build the flow
flow = Flows.Flow(vf; reltol=1e-8)

# 3. Integrate — point form (final state)
xf = flow(0.0, [1.0, 0.0], 1.0)

# 4. Integrate — trajectory form (full history)
sol = flow((0.0, 1.0), [1.0, 0.0])
t   = Trajectories.time_grid(sol)
x   = Trajectories.state(sol)              # callable: x(t) → state at time t
x(0.5)                                  # interpolate

Architecture

CTFlows is organised as a four-layer pipeline:

Data → Systems → Integrators → Flows → Trajectories

The shortcut Flows.Flow(data; opts...) collapses all pipeline steps into a single call. The explicit pipeline (build_system → build_integrator → build_flow) gives full control over each step.

Guides