CTSolvers.jl

CTSolvers.jl is the resolution layer of the control-toolbox ecosystem. It provides the infrastructure — solvers, modelers, integrators, and abstract problem types — used by upstream packages to solve optimal control problems.

CTSolvers and its consumers

CTSolvers provides the resolution infrastructure; it does not call it directly. Two packages build on top of it:

• CTDirect.jl — direct methods: discretizes continuous-time OCPs (defined in CTModels.jl) into finite-dimensional NLPs, then uses CTSolvers' Solvers and Modelers to solve them.

• CTFlows.jl — flows for indirect methods: builds Hamiltonian flows from ODE systems and integrates them with CTSolvers' Integrators.

Note

The root package is OptimalControl.jl which aims to provide tools to model and solve optimal control problems with ordinary differential equations by direct and indirect methods, both on CPU and GPU.

Qualified Module Access

CTSolvers does not export functions directly. All functions and types are accessed via qualified module paths:

using CTSolvers
CTBase.Strategies.id(CTSolvers.Solvers.Ipopt)   # ✓ Qualified
CTSolvers.Optimization.build_model(prob, x0, m)  # ✓ Qualified

Module overview

Module	Responsibility
Optimization	Abstract problem types (AbstractOptimizationProblem, BuiltModel, NoCache), build_model/build_solution generic functions
Modelers	Modelers.ADNLP, Modelers.Exa — NLP backend adapters
DOCP	DiscretizedModel — concrete problem type, pairs OCP with its discretizer (from CTDirect.jl)
Solvers	Solvers.Ipopt, Solvers.MadNLP, Solvers.MadNCL, Solvers.Knitro, Solvers.Uno — NLP solver wrappers
Integrators	Integrators.SciML — ODE integrator wrapper

How this documentation is organized

• Getting Started — installation and a quick-start walkthrough.

• Architecture — module overview, type hierarchies, data flow, and design patterns.

• Developer Guides — step-by-step tutorials for implementing each component type:

  • Implementing a Solver — tag dispatch, extension pattern, CommonSolve integration

  • Implementing an Integrator — SciML wrapper, integration result types

  • Implementing a Modeler — strategy options, build_model/build_solution dispatch

  • Implementing an Optimization Problem — AbstractOptimizationProblem contract, DiscretizedModel

  • Error Messages Reference — all exception types with examples and fixes

• API Reference — auto-generated documentation for all public and private symbols.

Ask DeepWiki

offers an interactive, AI-generated overview of this codebase. Answers may be inaccurate — use this reference documentation as the source of truth.